fritz kept the letter from wurzburg unopened in his hand.

"it's not from minna," he said; "the handwriting is strange to me. perhaps my father knows something about it." he turned to his father's letter; read it; and handed it to me without a word of remark.

mr. keller wrote briefly as follows:—

"the enclosed letter has reached me by post, as you perceive, with written instructions to forward it to my son. the laws of honor guide me just as absolutely in my relations with my son as in my relations with any other gentleman. i forward the letter to you exactly as i have received it. but i cannot avoid noticing the postmark of the city in which the widow fontaine and her daughter are still living. if either minna or her mother be the person who writes to you, i must say plainly that i forbid your entering into any correspondence with them. the two families shall never be connected by marriage while i live. understand, my dear son, that this is said in your own best interests, and said, therefore, from the heart of your father who loves you."

while i was reading these lines fritz had opened the letter from wurzburg. "it's long enough, at any rate," he said, turning over the closely-written pages to find the signature at the end.

"well?" i asked.

"well," fritz repeated, "it's an anonymous letter. the signature is 'your unknown friend.'"

"perhaps it relates to miss minna, or to her mother," i suggested. fritz turned back to the first page and looked up at me, red with anger. "more abominable slanders! more lies about minna's mother!" he burst out. "come here, david. look at it with me. what do you say? is it the writing of a woman or a man?"

the writing was so carefully disguised that it was impossible to answer his question. the letter (like the rest of the correspondence connected with this narrative) has been copied in duplicate and placed at my disposal. i reproduce it here for reasons which will presently explain themselves—altering nothing, not even the vulgar familiarity of the address.

"my good fellow, you once did me a kindness a long time since. never mind what it was or who i am. i mean to do you a kindness in return. let that be enough.

"you are in love with 'jezebel's daughter.' now, don't be angry! i know you believe jezebel to be a deeply-injured woman; i know you have been foolish enough to fight duels at wurzburg in defense of her character.

"it is enough for you that she is a fond mother, and that her innocent daughter loves her dearly. i don't deny that she is a fond mother; but is the maternal instinct enough of itself to answer for a woman? why, fritz, a cat is a fond mother; but a cat scratches and swears for all that! and poor simple little minna, who can see no harm in anybody, who can't discover wickedness when it stares her in the face—is she a trustworthy witness to the widow's character? bah!

"don't tear up my letter in a rage; i am not going to argue the question with you any further. certain criminal circumstances have come to my knowledge, which point straight to this woman. i shall plainly relate those circumstances, out of my true regard for you, in the fervent hope that i may open your eyes to the truth.

"let us go back to the death of doctor-professor fontaine, at his apartments in the university of wurzburg, on the 3rd of september, in the present year 1828.

"the poor man died of typhoid fever, as you know—and died in debt, through no extravagance on his own part, as you also know. he had outlived all his own relatives, and had no pecuniary hopes or expectations from anyone. under these circumstances, he could only leave the written expression of his last wishes, in place of a will.

"this document committed his widow and child to the care of his widow's relations, in terms of respectful entreaty. speaking next of himself, he directed that he should be buried with the strictest economy, so that he might cost the university as little as possible. thirdly, and lastly, he appointed one of his brother professors to act as his sole executor, in disposing of those contents of his laboratory which were his own property at the time of his death.

"the written instructions to his executor are of such serious importance that i feel it my duty to copy them for you, word for word.

"thus they begin:—

"'i hereby appoint my dear old friend and colleague, professor stein—now absent for a while at munich, on university business—to act as my sole representative in the disposal of the contents of my laboratory, after my death. the various objects used in my chemical investigations, which are my own private property, will be all found arranged on the long deal table that stands between the two windows. they are to be offered for sale to my successor, in the first instance. if he declines to purchase them, they can then be sent to munich, to be sold separately by the manufacturer, as occasion may offer. the furniture of the laboratory, both movable and stationary, belongs entirely to the university, excepting the contents of an iron safe built into the south wall of the room. as to these, which are my own sole property, i seriously enjoin my executor and representative to follow my instructions to the letter:—

"'(1) professor stein will take care to be accompanied by a competent witness, when he opens the safe in the wall.

"'(2) the witness will take down in writing, from the dictation of professor stein, an exact list of the contents of the safe. these are:—bottles containing drugs, tin cases containing powders, and a small medicine-chest, having six compartments, each occupied by a labeled bottle, holding a liquid preparation.

"'(3) the written list being complete, i desire professor stein to empty every one of the bottles and cases, including the bottles in the medicine-chest, into the laboratory sink, with his own hands. he is also to be especially careful to destroy the labels on the bottles in the medicine-chest. these things done, he will sign the list, stating that the work of destruction is accomplished; and the witness present will add his signature. the document, thus attested, is to be placed in the care of the secretary to the university.

"'my object in leaving these instructions is simply to prevent the dangerous results which might follow any meddling with my chemical preparations, after my death.

"'in almost every instance, these preparations are of a poisonous nature. having made this statement, let me add, in justice to myself, that the sole motive for my investigations has been the good of my fellow-creatures.

"'i have been anxious, in the first place, to enlarge the list of curative medicines having poison for one of their ingredients. i have attempted, in the second place, to discover antidotes to the deadly action of those poisons, which (in cases of crime or accident) might be the means of saving life.

"'if i had been spared for a few years longer, i should so far have completed my labors as to have ventured on leaving them to be introduced to the medical profession by my successor. as it is—excepting one instance, in which i ran the risk, and was happily enabled to preserve the life of a poisoned man—i have not had time so completely to verify my theories, by practical experiment, as to justify me in revealing my discoveries to the scientific world for the benefit of mankind.

"'under these circumstances, i am resigned to the sacrifice of my ambition—i only desire to do no harm. if any of my preparations, and more particularly those in the medicine-chest, fell into ignorant or wicked hands, i tremble when i think of the consequences which might follow. my one regret is, that i have not strength enough to rise from my bed, and do the good work of destruction myself. my friend and executor will take my place.

"'the key of the laboratory door, and the key of the safe, will be secured this day in the presence of my medical attendant, in a small wooden box. the box will be sealed (before the same witness) with my own seal. i shall keep it under my pillow, to give it myself to professor stein, if i live until he returns from munich.

"'if i die while my executor is still absent, my beloved wife is the one person in the world whom i can implicitly trust to take charge of the sealed box. she will give it to professor stein, immediately on his return to wurzburg; together with these instructions, which will be placed in the box along with the keys.'"

"there are the instructions, friend fritz! they are no secret now. the professor has felt it his duty to make them public in a court of law, in consequence of the events which followed doctor fontaine's death. you are interested in those events, and you shall be made acquainted with them before i close my letter.

"professor stein returned from munich too late to receive the box from the hands of his friend and colleague. it was presented to him by the widow fontaine, in accordance with her late husband's wishes.

"the professor broke the seal. having read his instructions, he followed them to the letter, the same day.

"accompanied by the secretary to the university, as a witness, he opened the laboratory door. leaving the sale of the objects on the table to be provided for at a later date, he proceeded at once to take the list of the bottles and cases, whose contents he was bound to destroy. on opening the safe, these objects were found as the instructions led him to anticipate: the dust lying thick on them vouched for their having been left undisturbed. the list being completed, the contents of the bottles and cases were thereupon thrown away by the professor's own hand.

"on looking next, however, for the medicine-chest, no such thing was to be discovered in the safe. the laboratory was searched from end to end, on the chance that some mistake had been made. still no medicine-chest was to be found.

"upon this the widow fontaine was questioned. did she know what had become of the medicine-chest? she was not even aware that such a thing existed. had she been careful to keep the sealed box so safely that no other person could get at it? certainly! she had kept it locked in one of her drawers, and the key in her pocket.

"the lock of the drawer, and the locks of the laboratory door and the safe, were examined. they showed no sign of having been tampered with. persons employed in the university, who were certain to know, were asked if duplicate keys existed, and all united in answering in the negative. the medical attendant was examined, and declared that it was physically impossible for doctor fontaine to have left his bed, and visited the laboratory, between the time of writing his instructions and the time of his death.

"while these investigations were proceeding, doctor fontaine's senior assistant obtained leave to examine through a microscope the sealing-wax left on the box which had contained the keys.

"the result of this examination, and of the chemical analyses which followed, proved that two different kinds of sealing-wax (both of the same red color, superficially viewed) had been used on the seal of the box—an undermost layer of one kind of wax, and an uppermost layer of another, mingled with the undermost in certain places only. the plain inference followed that the doctor's sealing-wax had been softened by heat so as to allow of the opening of the box, and that new sealing-wax had been afterwards added, and impressed by the doctor's seal so that the executor might suspect nothing. here, again, the evidence of the medical attendant (present at the time) proved that doctor fontaine had only used one stick of sealing-wax to secure the box. the seal itself was found in the possession of the widow; placed carelessly in the china tray in which she kept her rings after taking them off for the night.

"the affair is still under judicial investigation. i will not trouble you by reporting the further proceedings in detail.

"of course, widow fontaine awaits the result of the investigation with the composure of conscious innocence. of course, she has not only submitted to an examination of her lodgings, but has insisted on it. of course, no red sealing-wax and no medicine-chest have been found. of course, some thief unknown, for some purpose quite inconceivable, got at the box and the seal, between the doctor's death and the return of the professor from munich, and read the instructions and stole the terrible medicine-chest. such is the theory adopted by the defense. if you can believe it—then i have written in vain. if, on the other hand, you are the sensible young man i take you to be, follow my advice. pity poor little minna as much as you please, but look out for another young lady with an unimpeachable mother; and think yourself lucky to have two such advisers as your excellent father, and your unknown friend."