a living interrogation-point and a born investigator from childhood, edison has never been without a laboratory of some kind for upward of half a century.

in youthful years, as already described in this book, he became ardently interested in chemistry, and even at the early age of twelve felt the necessity for a special nook of his own, where he could satisfy his unconvinced mind of the correctness or inaccuracy of statements and experiments contained in the few technical books then at his command.

ordinarily he was like other normal lads of his age—full of boyish, hearty enjoyments—but withal possessed of an unquenchable spirit of inquiry and an insatiable desire for knowledge. being blessed with a wise and discerning mother, his aspirations were encouraged; and he was allowed a corner in her cellar. it is fair to offer tribute here to her bravery as well as to her wisdom, for at times she was in mortal terror lest the precocious experimenter below should, in his inexperience, make some awful combination that would explode and bring down the house in ruins on himself and the rest of the family.

fortunately no such catastrophe happened, but young edison worked away in his embryonic laboratory, satisfying his soul and incidentally depleting his limited pocket-money to the vanishing-point. it was, indeed, owing to this latter circumstance that in a year or two his aspirations necessitated an increase of revenue; and a consequent determination to earn some money for himself led to his first real commercial enterprise as "candy butcher" on the grand trunk railroad, already mentioned in a previous chapter. it has also been related how his precious laboratory was transferred to the train; how he and it were subsequently expelled; and how it was re-established in his home, where he continued studies and experiments until the beginning of his career as a telegraph operator.

the nomadic life of the next few years did not lessen his devotion to study; but it stood seriously in the way of satisfying the ever-present craving for a laboratory. the lack of such a place never prevented experimentation, however, as long as he had a dollar in his pocket and some available "hole in the wall." with the turning of the tide of fortune that suddenly carried him, in new york in 1869, from poverty to the opulence of $300 a month, he drew nearer to a realization of his cherished ambition in having money, place, and some time (stolen from sleep) for more serious experimenting. thus matters continued until, at about the age of twenty-two, edison's inventions had brought him a relatively large sum of money, and he became a very busy manufacturer, and lessee of a large shop in newark, new jersey.

now, for the first time since leaving that boyish laboratory in the old home at port huron, edison had a place of his own to work in, to think in; but no one in any way acquainted with newark as a swarming centre of miscellaneous and multitudinous industries would recommend it as a cloistered retreat for brooding reverie and introspection, favorable to creative effort. some people revel in surroundings of hustle and bustle, and find therein no hindrance to great accomplishment. the electrical genius of newark is edward weston, who has thriven amid its turmoil and there has developed his beautiful instruments of precision; just as brush worked out his arc-lighting system in cleveland; or even as faraday, surrounded by the din and roar of london, laid the intellectual foundations of the whole modern science of dynamic electricity. but edison, though deaf, could not make too hurried a retreat from newark to menlo park, where, as if to justify his change of base, vital inventions soon came thick and fast, year after year. the story of menlo has been told in another chapter, but the point was not emphasized that edison then, as later, tried hard to drop manufacturing. he would infinitely rather be philosopher than producer; but somehow the necessity of manufacturing is constantly thrust back upon him by a profound—perhaps finical—sense of dissatisfaction with what other people make for him. the world never saw a man more deeply and desperately convinced that nothing in it approaches perfection. edison is the doctrine of evolution incarnate, applied to mechanics. as to the removal from newark, he may be allowed to tell his own story: "i had a shop at newark in which i manufactured stock tickers and such things. when i moved to menlo park i took out only the machinery that would be necessary for experimental purposes and left the manufacturing machinery in the place. it consisted of many milling machines and other tools for duplicating. i rented this to a man who had formerly been my bookkeeper, and who thought he could make money out of manufacturing. there was about $10,000 worth of machinery. he was to pay me $2000 a year for the rent of the machinery and keep it in good order. after i moved to menlo park, i was very busy with the telephone and phonograph, and i paid no attention to this little arrangement. about three years afterward, it occurred to me that i had not heard at all from the man who had rented this machinery, so i thought i would go over to newark and see how things were going. when i got there, i found that instead of being a machine shop it was a hotel! i have since been utterly unable to find out what became of the man or the machinery." such incidents tend to justify edison in his rather cynical remark that he has always been able to improve machinery much quicker than men. all the way up he has had discouraging experiences. "one day while i was carrying on my work in newark, a wall street broker came from the city and said he was tired of the 'street,' and wanted to go into something real. he said he had plenty of money. he wanted some kind of a job to keep his mind off wall street. so we gave him a job as a 'mucker' in chemical experiments. the second night he was there he could not stand the long hours and fell asleep on a sofa. one of the boys took a bottle of bromine and opened it under the sofa. it floated up and produced a violent effect on the mucous membrane. the broker was taken with such a fit of coughing he burst a blood-vessel, and the man who let the bromine out got away and never came back. i suppose he thought there was going to be a death. but the broker lived, and left the next day; and i have never seen him since, either." edison tells also of another foolhardy laboratory trick of the same kind: "some of my assistants in those days were very green in the business, as i did not care whether they had had any experience or not. i generally tried to turn them loose. one day i got a new man, and told him to conduct a certain experiment. he got a quart of ether and started to boil it over a naked flame. of course it caught fire. the flame was about four feet in diameter and eleven feet high. we had to call out the fire department; and they came down and put a stream through the window. that let all the fumes and chemicals out and overcame the firemen; and there was the devil to pay. another time we experimented with a tub full of soapy water, and put hydrogen into it to make large bubbles. one of the boys, who was washing bottles in the place, had read in some book that hydrogen was explosive, so he proceeded to blow the tub up. there was about four inches of soap in the bottom of the tub, fourteen inches high; and he filled it with soap bubbles up to the brim. then he took a bamboo fish-pole, put a piece of paper at the end, and touched it off. it blew every window out of the place."

always a shrewd, observant, and kindly critic of character, edison tells many anecdotes of the men who gathered around him in various capacities at that quiet corner of new jersey—menlo park—and later at orange, in the llewellyn park laboratory; and these serve to supplement the main narrative by throwing vivid side-lights on the whole scene. here, for example, is a picture drawn by edison of a laboratory interlude—just a bit rabelaisian: "when experimenting at menlo park we had all the way from forty to fifty men. they worked all the time. each man was allowed from four to six hours' sleep. we had a man who kept tally, and when the time came for one to sleep, he was notified. at midnight we had lunch brought in and served at a long table at which the experimenters sat down. i also had an organ which i procured from hilbourne roosevelt—uncle of the ex-president—and we had a man play this organ while we ate our lunch. during the summertime, after we had made something which was successful, i used to engage a brick-sloop at perth amboy and take the whole crowd down to the fishing-banks on the atlantic for two days. on one occasion we got outside sandy hook on the banks and anchored. a breeze came up, the sea became rough, and a large number of the men were sick. there was straw in the bottom of the boat, which we all slept on. most of the men adjourned to this straw very sick. those who were not got a piece of rancid salt pork from the skipper, and cut a large, thick slice out of it. this was put on the end of a fish-hook and drawn across the men's faces. the smell was terrific, and the effect added to the hilarity of the excursion.

"i went down once with my father and two assistants for a little fishing inside sandy hook. for some reason or other the fishing was very poor. we anchored, and i started in to fish. after fishing for several hours there was not a single bite. the others wanted to pull up anchor, but i fished two days and two nights without a bite, until they pulled up anchor and went away. i would not give up. i was going to catch that fish if it took a week."

this is general. let us quote one or two piquant personal observations of a more specific nature as to the odd characters edison drew around him in his experimenting. "down at menlo park a man came in one day and wanted a job. he was a sailor. i hadn't any particular work to give him, but i had a number of small induction coils, and to give him something to do i told him to fix them up and sell them among his sailor friends. they were fixed up, and he went over to new york and sold them all. he was an extraordinary fellow. his name was adams. one day i asked him how long it was since he had been to sea, and he replied two or three years. i asked him how he had made a living in the mean time, before he came to menlo park. he said he made a pretty good living by going around to different clinics and getting $10 at each clinic, because of having the worst case of heart-disease on record. i told him if that was the case he would have to be very careful around the laboratory. i had him there to help in experimenting, and the heart-disease did not seem to bother him at all.

"it appeared that he had once been a slaver; and altogether he was a tough character. having no other man i could spare at that time, i sent him over with my carbon transmitter telephone to exhibit it in england. it was exhibited before the post-office authorities. professor hughes spent an afternoon in examining the apparatus, and in about a month came out with his microphone, which was absolutely nothing more nor less than my exact invention. but no mention was made of the fact that, just previously, he had seen the whole of my apparatus. adams stayed over in europe connected with the telephone for several years, and finally died of too much whiskey—but not of heart-disease. this shows how whiskey is the more dangerous of the two.

"adams said that at one time he was aboard a coffee-ship in the harbor of santos, brazil. he fell down a hatchway and broke his arm. they took him up to the hospital—a portuguese one—where he could not speak the language, and they did not understand english. they treated him for two weeks for yellow fever! he was certainly the most profane man we ever had around the laboratory. he stood high in his class."

and there were others of a different stripe. "we had a man with us at menlo called segredor. he was a queer kind of fellow. the men got in the habit of plaguing him; and, finally, one day he said to the assembled experimenters in the top room of the laboratory: 'the next man that does it, i will kill him.' they paid no attention to this, and next day one of them made some sarcastic remark to him. segredor made a start for his boarding-house, and when they saw him coming back up the hill with a gun, they knew there would be trouble, so they all made for the woods. one of the men went back and mollified him. he returned to his work; but he was not teased any more. at last, when i sent men out hunting for bamboo, i dispatched segredor to cuba. he arrived in havana on tuesday, and on the friday following he was buried, having died of the black vomit. on the receipt of the news of his death, half a dozen of the men wanted his job, but my searcher in the astor library reported that the chances of finding the right kind of bamboo for lamps in cuba were very small; so i did not send a substitute."

another thumb-nail sketch made of one of his associates is this: "when experimenting with vacuum-pumps to exhaust the incandescent lamps, i required some very delicate and close manipulation of glass, and hired a german glass-blower who was said to be the most expert man of his kind in the united states. he was the only one who could make clinical thermometers. he was the most extraordinarily conceited man i have ever come across. his conceit was so enormous, life was made a burden to him by all the boys around the laboratory. he once said that he was educated in a university where all the students belonged to families of the aristocracy; and the highest class in the university all wore little red caps. he said he wore one."

of somewhat different caliber was "honest" john kruesi, who first made his mark at menlo park, and of whom edison says: "one of the workmen i had at menlo park was john kruesi, who afterward became, from his experience, engineer of the lighting station, and subsequently engineer of the edison general electric works at schenectady. kruesi was very exact in his expressions. at the time we were promoting and putting up electric-light stations in pennsylvania, new york, and new england, there would be delegations of different people who proposed to pay for these stations. they would come to our office in new york, at '65,' to talk over the specifications, the cost, and other things. at first, mr. kruesi was brought in, but whenever a statement was made which he could not understand or did not believe could be substantiated, he would blurt right out among these prospects that he didn't believe it. finally it disturbed these committees so much, and raised so many doubts in their minds, that one of my chief associates said: 'here, kruesi, we don't want you to come to these meetings any longer. you are too painfully honest.' i said to him: 'we always tell the truth. it may be deferred truth, but it is the truth.' he could not understand that."

various reasons conspired to cause the departure from menlo park midway in the eighties. for edison, in spite of the achievement with which its name will forever be connected, it had lost all its attractions and all its possibilities. it had been outgrown in many ways, and strange as the remark may seem, it was not until he had left it behind and had settled in orange, new jersey, that he can be said to have given definite shape to his life. he was only forty in 1887, and all that he had done up to that time, tremendous as much of it was, had worn a haphazard, bohemian air, with all the inconsequential freedom and crudeness somehow attaching to pioneer life. the development of the new laboratory in west orange, just at the foot of llewellyn park, on the orange mountains, not only marked the happy beginning of a period of perfect domestic and family life, but saw in the planning and equipment of a model laboratory plant the consummation of youthful dreams, and of the keen desire to enjoy resources adequate at any moment to whatever strain the fierce fervor of research might put upon them. curiously enough, while hitherto edison had sought to dissociate his experimenting from his manufacturing, here he determined to develop a large industry to which a thoroughly practical laboratory would be a central feature, and ever a source of suggestion and inspiration. edison's standpoint to-day is that an evil to be dreaded in manufacture is that of over-standardization, and that as soon as an article is perfect that is the time to begin improving it. but he who would improve must experiment.

the orange laboratory, as originally planned, consisted of a main building two hundred and fifty feet long and three stories in height, together with four other structures, each one hundred by twenty-five feet, and only one story in height. all these were substantially built of brick. the main building was divided into five chief divisions—the library, office, machine shops, experimental and chemical rooms, and stock-room. the use of the smaller buildings will be presently indicated.

surrounding the whole was erected a high picket fence with a gate placed on valley road. at this point a gate-house was provided and put in charge of a keeper, for then, as at the present time, edison was greatly sought after; and, in order to accomplish any work at all, he was obliged to deny himself to all but the most important callers. the keeper of the gate was usually chosen with reference to his capacity for stony-hearted implacability and adherence to instructions; and this choice was admirably made in one instance when a new gateman, not yet thoroughly initiated, refused admittance to edison himself. it was of no use to try and explain. to the gateman every one was persona non grata without proper credentials, and edison had to wait outside until he could get some one to identify him.

on entering the main building the first doorway from the ample passage leads the visitor into a handsome library finished throughout in yellow pine, occupying the entire width of the building, and almost as broad as long. the centre of this spacious room is an open rectangular space about forty by twenty-five feet, rising clear about forty feet from the main floor to a panelled ceiling. around the sides of the room, bounding this open space, run two tiers of gallery, divided, as is the main floor beneath them; into alcoves of liberal dimensions. these alcoves are formed by racks extending from floor to ceiling, fitted with shelves, except on two sides of both galleries, where they are formed by a series of glass-fronted cabinets containing extensive collections of curious and beautiful mineralogical and geological specimens, among which is the notable tiffany-kunz collection of minerals acquired by edison some years ago. here and there in these cabinets may also be found a few models which he has used at times in his studies of anatomy and physiology.

the shelves on the remainder of the upper gallery and part of those on the first gallery are filled with countless thousands of specimens of ores and minerals of every conceivable kind gathered from all parts of the world, and all tagged and numbered. the remaining shelves of the first gallery are filled with current numbers (and some back numbers) of the numerous periodicals to which edison subscribes. here may be found the popular magazines, together with those of a technical nature relating to electricity, chemistry, engineering, mechanics, building, cement, building materials, drugs, water and gas, power, automobiles, railroads, aeronautics, philosophy, hygiene, physics, telegraphy, mining, metallurgy, metals, music, and others; also theatrical weeklies, as well as the proceedings and transactions of various learned and technical societies.

the first impression received as one enters on the main floor of the library and looks around is that of noble proportions and symmetry as a whole. the open central space of liberal dimensions and height, flanked by the galleries and relieved by four handsome electric-lighting fixtures suspended from the ceiling by long chains, conveys an idea of lofty spaciousness; while the huge open fireplace, surmounted by a great clock built into the wall, at one end of the room, the large rugs, the arm-chairs scattered around, the tables and chairs in the alcoves, give a general air of comfort combined with utility. in one of the larger alcoves, at the sunny end of the main hall, is edison's own desk, where he may usually be seen for a while in the early morning hours looking over his mail or otherwise busily working on matters requiring his attention.

at the opposite end of the room, not far from the open fireplace, is a long table surrounded by swivel desk-chairs. it is here that directors' meetings are sometimes held, and also where weighty matters are often discussed by edison at conference with his closer associates. it has been the privilege of the writers to be present at some of these conferences, not only as participants, but in some cases as lookers-on while awaiting their turn. on such occasions an interesting opportunity is offered to study edison in his intense and constructive moods. apparently oblivious to everything else, he will listen with concentrated mind and close attention, and then pour forth a perfect torrent of ideas and plans, and, if the occasion calls for it, will turn around to the table, seize a writing-pad and make sketch after sketch with lightning-like rapidity, tearing off each sheet as filled and tossing it aside to the floor. it is an ordinary indication that there has been an interesting meeting when the caretaker about fills a waste-basket with these discarded sketches.

directly opposite the main door is a beautiful marble statue purchased by edison at the paris exposition in 1889, on the occasion of his visit there. the statue, mounted on a base three feet high, is an allegorical representation of the supremacy of electric light over all other forms of illumination, carried out by the life-size figure of a youth with half-spread wings seated upon the ruins of a street gas-lamp, holding triumphantly high above his head an electric incandescent lamp. grouped about his feet are a gear-wheel, voltaic pile, telegraph key, and telephone. this work of art was executed by a. bordiga, of rome, held a prominent place in the department devoted to italian art at the paris exposition, and naturally appealed to edison as soon as he saw it.

in the middle distance, between the entrance door and this statue, has long stood a magnificent palm, but at the present writing it has been set aside to give place to a fine model of the first type of the edison poured cement house, which stands in a miniature artificial lawn upon a special table prepared for it; while on the floor at the foot of the table are specimens of the full-size molds in which the house will be cast.

the balustrades of the galleries and all other available places are filled with portraits of great scientists and men of achievement, as well as with pictures of historic and scientific interest. over the fireplace hangs a large photograph showing the edison cement plant in its entire length, flanked on one end of the mantel by a bust of humboldt, and on the other by a statuette of sandow, the latter having been presented to edison by the celebrated athlete after the visit he made to orange to pose for the motion pictures in the earliest days of their development. on looking up under the second gallery at this end is seen a great roll resting in sockets placed on each side of the room. this is a huge screen or curtain which may be drawn down to the floor to provide a means of projection for lantern slides or motion pictures, for the entertainment or instruction of edison and his guests. in one of the larger alcoves is a large terrestrial globe pivoted in its special stand, together with a relief map of the united states; and here and there are handsomely mounted specimens of underground conductors and electric welds that were made at the edison machine works at schenectady before it was merged into the general electric company. on two pedestals stand, respectively, two other mementoes of the works, one a fifteen-light dynamo of the edison type, and the other an elaborate electric fan—both of them gifts from associates or employees.

in noting these various objects of interest one must not lose sight of the fact that this part of the building is primarily a library, if indeed that fact did not at once impress itself by a glance at the well-filled unglazed book-shelves in the alcoves of the main floor. here edison's catholic taste in reading becomes apparent as one scans the titles of thousands of volumes ranged upon the shelves, for they include astronomy, botany, chemistry, dynamics, electricity, engineering, forestry, geology, geography, mechanics, mining, medicine, metallurgy, magnetism, philosophy, psychology, physics, steam, steam-engines, telegraphy, telephony, and many others. besides these there are the journals and proceedings of numerous technical societies; encyclopaedias of various kinds; bound series of important technical magazines; a collection of united states and foreign patents, embracing some hundreds of volumes, together with an extensive assortment of miscellaneous books of special and general interest. there is another big library up in the house on the hill—in fact, there are books upon books all over the home. and wherever they are, those books are read.

as one is about to pass out of the library attention is arrested by an incongruity in the form of a cot, which stands in an alcove near the door. here edison, throwing himself down, sometimes seeks a short rest during specially long working tours. sleep is practically instantaneous and profound, and he awakes in immediate and full possession of his faculties, arising from the cot and going directly "back to the job" without a moment's hesitation, just as a person wide awake would arise from a chair and proceed to attend to something previously determined upon.

immediately outside the library is the famous stock-room, about which much has been written and invented. its fame arose from the fact that edison planned it to be a repository of some quantity, great or small, of every known and possibly useful substance not readily perishable, together with the most complete assortment of chemicals and drugs that experience and knowledge could suggest. always strenuous in his experimentation, and the living embodiment of the spirit of the song, i want what i want when i want it, edison had known for years what it was to be obliged to wait, and sometimes lack, for some substance or chemical that he thought necessary to the success of an experiment. naturally impatient at any delay which interposed in his insistent and searching methods, and realizing the necessity of maintaining the inspiration attending his work at any time, he determined to have within his immediate reach the natural resources of the world.

hence it is not surprising to find the stock-room not only a museum, but a sample-room of nature, as well as a supply department. to a casual visitor the first view of this heterogeneous collection is quite bewildering, but on more mature examination it resolves itself into a natural classification—as, for instance, objects pertaining to various animals, birds, and fishes, such as skins, hides, hair, fur, feathers, wool, quills, down, bristles, teeth, bones, hoofs, horns, tusks, shells; natural products, such as woods, barks, roots, leaves, nuts, seeds, herbs, gums, grains, flours, meals, bran; also minerals in great assortment; mineral and vegetable oils, clay, mica, ozokerite, etc. in the line of textiles, cotton and silk threads in great variety, with woven goods of all kinds from cheese-cloth to silk plush. as for paper, there is everything in white and colored, from thinnest tissue up to the heaviest asbestos, even a few newspapers being always on hand. twines of all sizes, inks, waxes, cork, tar, resin, pitch, turpentine, asphalt, plumbago, glass in sheets and tubes; and a host of miscellaneous articles revealed on looking around the shelves, as well as an interminable collection of chemicals, including acids, alkalies, salts, reagents, every conceivable essential oil and all the thinkable extracts. it may be remarked that this collection includes the eighteen hundred or more fluorescent salts made by edison during his experimental search for the best material for a fluoroscope in the initial x-ray period. all known metals in form of sheet, rod and tube, and of great variety in thickness, are here found also, together with a most complete assortment of tools and accessories for machine shop and laboratory work.

the list is confined to the merest general mention of the scope of this remarkable and interesting collection, as specific details would stretch out into a catalogue of no small proportions. when it is stated, however, that a stock clerk is kept exceedingly busy all day answering the numerous and various demands upon him, the reader will appreciate that this comprehensive assortment is not merely a fad of edison's, but stands rather as a substantial tribute to his wide-angled view of possible requirements as his various investigations take him far afield. it has no counterpart in the world!

beyond the stock-room, and occupying about half the building on the same floor, lie a machine shop, engine-room, and boiler-room. this machine shop is well equipped, and in it is constantly employed a large force of mechanics whose time is occupied in constructing the heavier class of models and mechanical devices called for by the varied experiments and inventions always going on.

immediately above, on the second floor, is found another machine shop in which is maintained a corps of expert mechanics who are called upon to do work of greater precision and fineness, in the construction of tools and experimental models. this is the realm presided over lovingly by john f. ott, who has been edison's designer of mechanical devices for over forty years. he still continues to ply his craft with unabated skill and oversees the work of the mechanics as his productions are wrought into concrete shape.

in one of the many experimental-rooms lining the sides of the second floor may usually be seen his younger brother, fred ott, whose skill as a dexterous manipulator and ingenious mechanic has found ample scope for exercise during the thirty-two years of his service with edison, not only at the regular laboratories, but also at that connected with the inventor's winter home in florida. still another of the ott family, the son of john f., for some years past has been on the experimental staff of the orange laboratory. although possessing in no small degree the mechanical and manipulative skill of the family, he has chosen chemistry as his special domain, and may be found with the other chemists in one of the chemical-rooms.

on this same floor is the vacuum-pump room with a glass-blowers' room adjoining, both of them historic by reason of the strenuous work done on incandescent lamps and x-ray tubes within their walls. the tools and appliances are kept intact, for edison calls occasionally for their use in some of his later experiments, and there is a suspicion among the laboratory staff that some day he may resume work on incandescent lamps. adjacent to these rooms are several others devoted to physical and mechanical experiments, together with a draughting-room.

last to be mentioned, but the first in order as one leaves the head of the stairs leading up to this floor, is no. 12, edison's favorite room, where he will frequently be found. plain of aspect, being merely a space boarded off with tongued-and-grooved planks—as all the other rooms are—without ornament or floor covering, and containing only a few articles of cheap furniture, this room seems to exercise a nameless charm for him. the door is always open, and often he can be seen seated at a plain table in the centre of the room, deeply intent on some of the numerous problems in which he is interested. the table is usually pretty well filled with specimens or data of experimental results which have been put there for his examination. at the time of this writing these specimens consist largely of sections of positive elements of the storage battery, together with many samples of nickel hydrate, to which edison devotes deep study. close at hand is a microscope which is in frequent use by him in these investigations. around the room, on shelves, are hundreds of bottles each containing a small quantity of nickel hydrate made in as many different ways, each labelled correspondingly. always at hand will be found one or two of the laboratory note-books, with frequent entries or comments in the handwriting which once seen is never forgotten.

no. 12 is at times a chemical, a physical, or a mechanical room—occasionally a combination of all, while sometimes it might be called a consultation-room or clinic—for often edison may be seen there in animated conference with a group of his assistants; but its chief distinction lies in its being one of his favorite haunts, and in the fact that within its walls have been settled many of the perplexing problems and momentous questions that have brought about great changes in electrical and engineering arts during the twenty-odd years that have elapsed since the orange laboratory was built.

passing now to the top floor the visitor finds himself at the head of a broad hall running almost the entire length of the building, and lined mostly with glass-fronted cabinets containing a multitude of experimental incandescent lamps and an immense variety of models of phonographs, motors, telegraph and telephone apparatus, meters, and a host of other inventions upon which edison's energies have at one time and another been bent. here also are other cabinets containing old papers and records, while further along the wall are piled up boxes of historical models and instruments. in fact, this hallway, with its conglomerate contents, may well be considered a scientific attic. it is to be hoped that at no distant day these edisoniana will be assembled and arranged in a fireproof museum for the benefit of posterity.

in the front end of the building, and extending over the library, is a large room intended originally and used for a time as the phonograph music-hall for record-making, but now used only as an experimental-room for phonograph work, as the growth of the industry has necessitated a very much larger and more central place where records can be made on a commercial scale. even the experimental work imposes no slight burden on it. on each side of the hallway above mentioned, rooms are partitioned off and used for experimental work of various kinds, mostly phonographic, although on this floor are also located the storage-battery testing-room, a chemical and physical room and edison's private office, where all his personal correspondence and business affairs are conducted by his personal secretary, mr. h. f. miller. a visitor to this upper floor of the laboratory building cannot but be impressed with a consciousness of the incessant efforts that are being made to improve the reproducing qualities of the phonograph, as he hears from all sides the sounds of vocal and instrumental music constantly varying in volume and timbre, due to changes in the experimental devices under trial.

the traditions of the laboratory include cots placed in many of the rooms of these upper floors, but that was in the earlier years when the strenuous scenes of menlo park were repeated in the new quarters. edison and his closest associates were accustomed to carry their labors far into the wee sma' hours, and when physical nature demanded a respite from work, a short rest would be obtained by going to bed on a cot. one would naturally think that the wear and tear of this intense application, day after day and night after night, would have tended to induce a heaviness and gravity of demeanor in these busy men; but on the contrary, the old spirit of good-humor and prankishness was ever present, as its frequent outbursts manifested from time to time. one instance will serve as an illustration. one morning, about 2.30, the late charles batchelor announced that he was tired and would go to bed. leaving edison and the others busily working, he went out and returned quietly in slippered feet, with his nightgown on, the handle of a feather duster stuck down his back with the feathers waving over his head, and his face marked. with unearthly howls and shrieks, a l'indien, he pranced about the room, incidentally giving edison a scare that made him jump up from his work. he saw the joke quickly, however, and joined in the general merriment caused by this prank.

leaving the main building with its corps of busy experimenters, and coming out into the spacious yard, one notes the four long single-story brick structures mentioned above. the one nearest the valley road is called the galvanometer-room, and was originally intended by edison to be used for the most delicate and minute electrical measurements. in order to provide rigid resting-places for the numerous and elaborate instruments he had purchased for this purpose, the building was equipped along three-quarters of its length with solid pillars, or tables, of brick set deep in the earth. these were built up to a height of about two and a half feet, and each was surmounted with a single heavy slab of black marble. a cement floor was laid, and every precaution was taken to render the building free from all magnetic influences, so that it would be suitable for electrical work of the utmost accuracy and precision. hence, iron and steel were entirely eliminated in its construction, copper being used for fixtures for steam and water piping, and, indeed, for all other purposes where metal was employed.

this room was for many years the headquarters of edison's able assistant, dr. a. e. kennelly, now professor of electrical engineering in harvard university to whose energetic and capable management were intrusted many scientific investigations during his long sojourn at the laboratory. unfortunately, however, for the continued success of edison's elaborate plans, he had not been many years established in the laboratory before a trolley road through west orange was projected and built, the line passing in front of the plant and within seventy-five feet of the galvanometer-room, thus making it practically impossible to use it for the delicate purposes for which it was originally intended.

for some time past it has been used for photography and some special experiments on motion pictures as well as for demonstrations connected with physical research; but some reminders of its old-time glory still remain in evidence. in lofty and capacious glass-enclosed cabinets, in company with numerous models of edison's inventions, repose many of the costly and elaborate instruments rendered useless by the ubiquitous trolley. instruments are all about, on walls, tables, and shelves, the photometer is covered up; induction coils of various capacities, with other electrical paraphernalia, lie around, almost as if the experimenter were absent for a few days but would soon return and resume his work.

in numbering the group of buildings, the galvanometer-room is no. 1, while the other single-story structures are numbered respectively 2, 3, and 4. on passing out of no. 1 and proceeding to the succeeding building is noticed, between the two, a garage of ample dimensions and a smaller structure, at the door of which stands a concrete-mixer. in this small building edison has made some of his most important experiments in the process of working out his plans for the poured house. it is in this little place that there was developed the remarkable mixture which is to play so vital a part in the successful construction of these everlasting homes for living millions.

drawing near to building no. 2, olfactory evidence presents itself of the immediate vicinity of a chemical laboratory. this is confirmed as one enters the door and finds that the entire building is devoted to chemistry. long rows of shelves and cabinets filled with chemicals line the room; a profusion of retorts, alembics, filters, and other chemical apparatus on numerous tables and stands, greet the eye, while a corps of experimenters may be seen busy in the preparation of various combinations, some of which are boiling or otherwise cooking under their dexterous manipulation.

it would not require many visits to discover that in this room, also, edison has a favorite nook. down at the far end in a corner are a plain little table and chair, and here he is often to be found deeply immersed in a study of the many experiments that are being conducted. not infrequently he is actively engaged in the manipulation of some compound of special intricacy, whose results might be illuminative of obscure facts not patent to others than himself. here, too, is a select little library of chemical literature.

the next building, no. 3, has a double mission—the farther half being partitioned off for a pattern-making shop, while the other half is used as a store-room for chemicals in quantity and for chemical apparatus and utensils. a grimly humorous incident, as related by one of the laboratory staff, attaches to no. 3. it seems that some time ago one of the helpers in the chemical department, an excitable foreigner, became dissatisfied with his wages, and after making an unsuccessful application for an increase, rushed in desperation to edison, and said "eef i not get more money i go to take ze cyanide potassia." edison gave him one quick, searching glance and, detecting a bluff, replied in an offhand manner: "there's a five-pound bottle in no. 3," and turned to his work again. the foreigner did not go to get the cyanide, but gave up his job.

the last of these original buildings, no. 4, was used for many years in edison's ore-concentrating experiments, and also for rough-and-ready operations of other kinds, such as furnace work and the like. at the present writing it is used as a general stock-room.

in the foregoing details, the reader has been afforded but a passing glance at the great practical working equipment which constitutes the theatre of edison's activities, for, in taking a general view of such a unique and comprehensive laboratory plant, its salient features only can be touched upon to advantage. it would be but repetition to enumerate here the practical results of the laboratory work during the past two decades, as they appear on other pages of this work. nor can one assume for a moment that the history of edison's laboratory is a closed book. on the contrary, its territorial boundaries have been increasing step by step with the enlargement of its labors, until now it has been obliged to go outside its own proper domains to occupy some space in and about the great edison industrial buildings and space immediately adjacent. it must be borne in mind that the laboratory is only the core of a group of buildings devoted to production on a huge scale by hundreds of artisans.

incidental mention has already been made of the laboratory at edison's winter residence in florida, where he goes annually to spend a month or six weeks. this is a miniature copy of the orange laboratory, with its machine shop, chemical-room, and general experimental department. while it is only in use during his sojourn there, and carries no extensive corps of assistants, the work done in it is not of a perfunctory nature, but is a continuation of his regular activities, and serves to keep him in touch with the progress of experiments at orange, and enables him to give instructions for their variation and continuance as their scope is expanded by his own investigations made while enjoying what he calls "vacation." what edison in florida speaks of as "loafing" would be for most of us extreme and healthy activity in the cooler far north.

a word or two may be devoted to the visitors received at the laboratory, and to the correspondence. it might be injudicious to gauge the greatness of a man by the number of his callers or his letters; but they are at least an indication of the degree to which he interests the world. in both respects, for these forty years, edison has been a striking example of the manner in which the sentiment of hero-worship can manifest itself, and of the deep desire of curiosity to get satisfaction by personal observation or contact. edison's mail, like that of most well-known men, is extremely large, but composed in no small degree of letters—thousands of them yearly—that concern only the writers, and might well go to the waste-paper basket without prolonged consideration. the serious and important part of the mail, some personal and some business, occupies the attention of several men; all such letters finding their way promptly into the proper channels, often with a pithy endorsement by edison scribbled on the margin. what to do with a host of others it is often difficult to decide, even when written by "cranks," who imagine themselves subject to strange electrical ailments from which edison alone can relieve them. many people write asking his opinion as to a certain invention, or offering him an interest in it if he will work it out. other people abroad ask help in locating lost relatives; and many want advice as to what they shall do with their sons, frequently budding geniuses whose ability to wire a bell has demonstrated unusual qualities. a great many persons want autographs, and some would like photographs. the amazing thing about it all is that this flood of miscellaneous letters flows on in one steady, uninterrupted stream, year in and year out; always a curious psychological study in its variety and volume; and ever a proof of the fact that once a man has become established as a personality in the public eye and mind, nothing can stop the tide of correspondence that will deluge him.

it is generally, in the nature of things, easier to write a letter than to make a call; and the semi-retirement of edison at a distance of an hour by train from new york stands as a means of protection to him against those who would certainly present their respects in person, if he could be got at without trouble. but it may be seriously questioned whether in the aggregate edison's visitors are less numerous or less time-consuming than his epistolary besiegers. it is the common experience of any visitor to the laboratory that there are usually several persons ahead of him, no matter what the hour of the day, and some whose business has been sufficiently vital to get them inside the porter's gate, or even into the big library and lounging-room. celebrities of all kinds and distinguished foreigners are numerous—princes, noblemen, ambassadors, artists, litterateurs, scientists, financiers, women. a very large part of the visiting is done by scientific bodies and societies; and then the whole place will be turned over to hundreds of eager, well-dressed men and women, anxious to see everything and to be photographed in the big courtyard around the central hero. nor are these groups and delegations limited to this country, for even large parties of english, dutch, italian, or japanese visitors come from time to time, and are greeted with the same ready hospitality, although edison, it is easy to see, is torn between the conflicting emotions of a desire to be courteous, and an anxiety to guard the precious hours of work, or watch the critical stage of a new experiment.

one distinct group of visitors has always been constituted by the "newspaper men." hardly a day goes by that the journals do not contain some reference to edison's work or remarks; and the items are generally based on an interview. the reporters are never away from the laboratory very long; for if they have no actual mission of inquiry, there is always the chance of a good story being secured offhand; and the easy, inveterate good-nature of edison toward reporters is proverbial in the craft. indeed, it must be stated here that once in a while this confidence has been abused; that stories have been published utterly without foundation; that interviews have been printed which never took place; that articles with edison's name as author have been widely circulated, although he never saw them; and that in such ways he has suffered directly. but such occasional incidents tend in no wise to lessen edison's warm admiration of the press or his readiness to avail himself of it whenever a representative goes over to orange to get the truth or the real facts in regard to any matter of public importance. as for the newspaper clippings containing such articles, or others in which edison's name appears—they are literally like sands of the sea-shore for number; and the archives of the laboratory that preserve only a very minute percentage of them are a further demonstration of what publicity means, where a figure like edison is concerned.