them read aloud to me. The practice which I had had, as already remarked, made this method of work so familiar to me that for works which are not of an artistic character, I prefer reading aloud to reading by touch.

However, as regards inquiries of this kind, I will not endeavor to deny that they present real difficulties. In the first place, and before all else, the impossibility of running over the matter is the great drawback to being read to aloud. The eye is quick to scrutinize a page, eliminate the whole of a useless chapter, and make sure that it contains nothing of any interest. Nothing can replace the eye for this purpose. It is necessary to resolve to listen carefully to useless developments for fear of imprudently skipping over an important idea. When I risked skipping passages, it was necessary that they should be short. It was necessary, indeed, to know all the different directions which the argument took. When one direction was sterile it could be abandoned, but it was important not to pass the exact point where the thought entered on a new path. Sometimes I employed a signal (a stroke of a ruler on the table, for example) for interrupting an introductory sentence, and it was understood that my reader was to begin further along, according to the character of the book, either at the beginning of the following sentence or at the next line, or five or six lines below. But these expedients were only moderately successful and had to be used very conservatively. Another difficulty is that borrowed eyes have never the docility of those which are under the direction of one's own will. A secretary, however devoted, grows weary of an extremely monotonous task, the interest of which escapes him. I do not attempt, therefore, to minimize the difficulties which a blind person encounters in such work. Taking all in all, however, they are difficulties only and not insurmountable obstacles. To succeed, it is necessary to have a little more patience, a little more perseverance, that is all.

Chronological researches can be made in the same way, and when the investigations of sources and chronology were completed, nothing remained to be done except to concentrate the results, assemble and condense them, and to make clear by their light the evolution of Montaigne's thought. This was merely a matter of reflection, the most agreeable task of all, because it was carried on without the use of books or any extraneous aid, and because it was all mental and depended on myself alone.

For the easy maturing of this reflection my memoranda in "braille " were both necessary and sufficient. I have already shown how easy their handling was to me. I believe that in this regard the blind man does not suffer from any inferiority, and the more he exercises his faculty of concentration the easier his task becomes.

Finally, we come to the work of editing. So many blind persons have published and are publishing remarkable articles and works that I have nothing really new to say on this subject. The editing of a work of erudition scarcely presents more difficulties than for a popular work. It merely requires more precision as concerns numbers, masses of dates-all things which require scrupulous care. It presupposes above all a mass of notes at the bottom of the pages, references to texts, and documentary proofs. All that may take one by surprise at first, but, by means of the notes in "braille," it is always possible, without too much labor, to attain a rigorous exactness. My volumes are studded with figures and exact references. My extracts having been made methodically, and the results drawn from them carefully recorded with all the indications arranged in proportion to and in accordance with the circumstances, it was easy for me to support my assertions with the critical proof which they demanded. There again it sufficed for me to refer to my memoranda, where everything was noted.

As to the mechanical execution and the actual composition, two methods were open to me. I could write out the work in "braille” in such a way that I could read and correct the matter myself, and turn the copy over to a typewriter to put into type, or I could copy my rough draft again on my own typewriter. I have used both methods, sometimes preferring the one and sometimes the other, according to circumstances. When I had to do with particularly difficult pages, requiring special accuracy, it seemed to me better to make a rough draft in relief, in order to be able to consider and compare it freely. For ordinary passages I much preferred the typewriter from the first.

One may be surprised that the rough drafts in "braille" were not always preferred. The writing, in spite of numerous abbreviations, was rather slow, and, furthermore, required a certain expense of physical energy. These two circumstances lessen the buoyancy of the mind and divert attention from the work of composition toward the details of mechanical execution. I am aware that some blind persons are less sensible of these inconveniences, but I know that there are others like myself who find themselves disconcerted by them. Typewriting, on the contrary, is quick and easy. It accompanies but does not interfere with the flow of the mind, which is scarcely conscious of its very flexible mechanism. Doubtless a person who can see finds it difficult to understand how anyone can write without being able to read over the paragraphs that are finished. I find that habit triumphs over this difficulty—at all events, with me it was a triumph without labor. The care involved in a methodical and rather rigid composition is in part the cause. When one has his plan well in mind, with even the details in order, one does not lose the thread of its

development, however lacking in exactness one's memory may be. It was very rarely that I found it necessary to seek the aid of other eyes to find my place, or to recall the form which I had given to any preceding sentences. Frequently I suspended the editorial work in the midst of the development of an idea. I left the sheet in the machine and sometimes after an interruption of forty-eight hours, or even more, took up the thought again without hesitation at the point at which I had left it. Moreover, I did not deprive myself of the opportunity of correction. The editing over, I had the matter read to me as many times as was necessary, dictating to my secretary modifications and sometimes very numerous additions, and adding everywhere a thousand finishing touches. I believe that I can say that my style was not less imperfect when I wrote the first draft in "braille." On the contrary, if it was perhaps a little more vigorous, it was also rather stiffer.

Finally, and this is what I particularly wish to note, the elaboration of these 1,250 very compact pages did not by any means cause me the prodigious labor that one might naturally expect. The one part which was long and tedious was the extensive preparation, all that which did not appear, the documentation which served as the basis of the work. I retain the hope that anyone who has followed my exposition is convinced that the undertaking can be carried on without any great difficulty and that the methods which are open to the blind lend themselves perfectly to its accomplishment. They have given me, I believe, means of conforming exactly to the course that any person who can see, desiring to treat of the same subject with accuracy, would be compelled to follow. In all my proceedings I have invented nothing. Any person with sight would, I think, be compelled to use some form of memoranda analogous to mine. I simply adapted a common and almost necessary method, I may say, to the special conditions of the blind. This adaptation was a very simple one and did not demand any great effort of the imagination. It was developed little by little, by successive steps, in accordance with the needs. It sprang in a certain way from circumstances.

My design, as one may suppose, is not to incite the blind to engage in the production of works of erudition. To succeed in this it is absolutely necessary to have the taste, the passion for learning, and most fortunately few persons are afflicted with this malady. What a strange life it would be if we were all metamorphosed into bookworms! Very fortunately, too, there are other works more accessible to the blind in which they have less trouble in rivaling those who In all that I have recounted it is not necessary to see an example, but an experience-an experience which, certes, will not surprise the blind (who, at least, will see that everything here men

can see.

tioned is quite simple), but may, perhaps, suggest to them some useful observations on certain applications of their own peculiar methods of work. It is, however, addressed especially to those who have sight. With so many other experiences which are renewed every day, it will contribute, perhaps, its little part to inspire them with more equitable judgments on the blind. It requires such an unending array of facts to combat a prejudice and to cause it to retreat step by step that we can never have enough. This will serve as one among many. Let us also hope that it will make an impression on the ranks of the enemy and work for the common welfare.

In conclusion, it remains for me to excuse myself for having spoken at such great length about my own affairs, but if the "I" (that of Montaigne excepted) is nearly always objectionable, the reader will pardon me when he notes that, in spite of appearances, I have mentioned much less regarding my own personal work than regarding that of the blind in general. What I have done any other blind person might have done in my place. Our methods of work are common to all. I have wished, by means of one example, to show the flexibility of our methods. Perhaps, after having read the foregoing, all will understand better how much we appreciate the inventor of an alphabet to which we owe the major part of our culture and our intellectual pleasures.

H

THE RELATION OF MOSQUITOES, FLIES, TICKS, FLEAS, AND OTHER ARTHROPODS TO PATHOLOGY.

By G. MAROTEL.

It is a matter of common knowledge to-day that while there are many arthropods which live a free life, there are also many others which are parasites, causing in man and also especially in the domestic animals many and varied diseases, the origin and nature of some of which have been known for a long time. It would be banal to recall that phthiriasis is caused by lice, and that certain larvæ of Diptera, such as the œstrids, may occasion the disease called myasis.

This old pathogenic rôle, which has been taught to all the medical and veterinary generations of our time, is quite true. But it is not of this that I wish to speak. It is of a new rôle, brought to light only within the last ten years, the importance of which now grows greater every day, for scarcely a month passes, I might almost say not a week, that some work does not appear which adds some unknown fact or new theory relative to it.

It has to do with one of the questions which in the whole range of parasitic pathology can, with the greatest right, claim to be of practical importance. The danger from the arthropods is a direct consequence of their habits. It only exists in connection with those whose habits are to seek association with men and domestic animals, to bite them and to suck their blood.

Everyone knows that a number of species, such as mosquitoes and gadflies, pass a considerable part of their time in flying from one victim to another, in the same manner that bees wander from flower to flower. Let us suppose, then, that in the course of these wanderings one of them happens to fasten itself on an individual affected by a parasitic or bacterial disease, the agent of which lives in the blood. In sucking the blood it absorbs also the germs which are contained in it, and thus is infected. Should it then attack a healthy person there is danger that it will inoculate him with the disease. This is why

a Translated by permission from Annales de la Société d'Agriculture, Sciences et Industrie de Lyon, 1906, pp. 279-302.