pathogenic, and the theory seemed to be confirmed by experiment. The difficulty lay in the practical impossibility of the separation of these different forms and their isolation for study, until the method of isolation by gelatine came into use. A culture thus obtained may, of course be investigated at will. We grow different forms in gelatine and examine their peculiarities there; we grow them on potatoes and examine their peculiarities there, and so on in other ways. Perhaps in all of the different sorts of culture the peculiarities of the species will show themselves, but not always. Two forms which are different from each other may, on potatoes for instance, yield cultures substantially alike, while they behave dif ferently toward gelatine or agar. And if you carry any nearly allied forms through a whole series of cultures you will find more than one point in which they differ, and where the true peculiarities of the species come out. Having obtained these various kinds of cultures, it is, of course, easy to obtain from them specimens for staining and otherwise treating for microsopic use. They may be prepared by placing them upon a hollow slide, inverting a cover over it and sealing around the edges, so that the evaporation of a drop of the fluid cannot take place; and here the peculiarities of the growths, the formation of spores and all those matters which are so essential to a minute knowledge of the species may be worked out by an observer, without losing, if it is necessary to observe so closely, a moment's time in the investigation of any type from the start of a given spore until the next generation of the spores has been produced. Such cultures as that have been made, but it is impossible for us, of course, to bring them down here to show.

Finally, in the case of infectious bacteria, another range of experiments has to be entered upon in order to determine what we have and what is going to come from the bacilli, namely: experiments on infection. In this work on pathogenic bacteria you must catch your bacillus in flagrante delictu to secure a conviction. If you are going to make sure you have discovered the cause of disease it is not sufficient for you to show that the bacillus that you have discovered is an accompaniment of the disease, but you must show that when inoculated into certain animals it produces with uniformity (unless you can show reasons for lack of uniformity), the disease which you ascribe to its workings. There is the point at which many probable discoveries have thus far failed. The pneumonia

coccus, for instance, which I have shown, has not been proved to be uniformly capable of producing pneumonia. The cholera bacillus, perhaps, has not been proved to be the cause of Asiatic cholera, infectious experiments having failed in many cases, although they have succeeded in some. If, however, the discoveries in this line of research shall be confirmed, and shall be extended by experiments on other bacteria, and if it shall be found, as it seems not at al impossible, that these bacteria cause disease by producing each a separate poison within the body of the animal infected, it opens to us not only a large range of knowledge in the line of causes of disease, but also quite new possibilities for the cure of infectious diseases.

There is one more point upon which I wish to say a few words, a point on which, perhaps, I am more interested than in the purely scientific value of these studies, and that is their worth as a study preparatory to medicine. Of course the study of bacteria can scarcely be regarded by physicians as yet in the light of a necessity; but sometimes it may be necessary to diagnose a disease by the study of bacteria. It will rarely be necessary to diagnose a disease by means of cultures; so that we may say that the laboratory study of bacteria, for the working physician, is like a good deal of the anatomy that he learned in the medical school and like what he knows of histology, and is not so directly practical and important in his every-day work as many other studies which will readily occur to you. And yet even on the practical side the study of bacteria is of great importance to a physician. Of course we cannot and would not say that the whole science of hygiene begins and ends in bacteriology, as some enthusiastic devotees of that study would claim; and yet, both in relation to the causes of disease and in relation to hygiene, the study of bacteria is of very considerable value, since in so many cases disease and health turn upon the presence or absence of these unwelcome guests. For the young man who is to be a surgeon the study of these germs seems to me of even more importance than for the general practitioner. No one can fairly appreciate the all-pervading presence of these germs until he has by a series of experiments of his own attempted to exclude themattempted to work out one form in a pure condition and to carry it in a pure condition through the various stages of its growth and development, and cultivate it in the media of which I have spoken.

He arrives then at a realization of the necessity for care; of the necessity of omitting nothing in the way of caution, in order to exclude these bacteria. By the study of these test tubes he learns the necessity for care which it is possible he will never learn elsewhere, except by practice on his patients.

From the scientific side, the study of bacteria offers great advantages The objects are susceptible of comparatively easy observation, but they need careful study and careful description and careful work of every sort in order to make them available as a means of education. And what makes them especially available for the purpose of the introductory study of medicine is the fact that the manipulations are comparatively simple. A student to do good scientific work in human or comparative anatomy has to learn a large number of manipulations. The thing in itself is difficult and the mechanical work of getting ready to do the thing occupies so much time, that for the ordinary college student it practically gives little mental training. In histology the elementary work may be done, but to carry it beyond the mere elementary work demands an acquaintance with the chemical properties and the constituents of tissues, and an amount of time and amount of work which men, who are occupied with other studies, are unable to put into it. Here, however, the methods are simple and he will encounter no great difficulty if he will follow his rules and use care. The microscopic work, too, although requiring care is comparatively simple, and the process of staining is simple and easy to follow out. That morphological simplicity which makes bacteria difficult to determine by their form makes the study under the microscope a comparatively easy thing. These two advantages, the necessity for scientific observation and the ease of technical manipulation concur in the study of bacteriology to a degree to which they scarcely come together in any other department of biological science. And as a third advantage we have the accessibility of material. The bacilli are always with us. They are to be obtained from any and every source, and the bacteria from any and every source are worthy of scientific observation, since so much is still to be learned in regard to even the best known and most common species.

I thank you gentlemen for your attention, and I should be glad to display these tubes to any of you who may choose to look at them.

ARTICLE XII.

ENTROPIUM: A FARTHER MODIFICATION IN THE OPERATION FOR ITS CURE.

BY EDWIN W. BARTLETT, M. D., OF MILWAUKEE.

Entropium consists of a curvature of the eyelid inwards, to such an extent that the eyelashes come into contact with the eyeball, and brush over its surface in the act of winking. A few lashes may touch the eyeball, or the lid may be so badly turned in, that in bad cases, all the lashes come into contact with the cornea.

Entropium is almost always preceded by granulated lids. The granulated conjunctiva has usually been almost entirely destroyed by degenerative changes following the natural course of a chronic inflammation, as in Trachoma, or by the over-zealous use of Nitrate of Silver, Sulphate of Copper, or other powerful remedies. The internal surface of the lid has slowly contracted, as any atrophied, burned or cicatricial tissue does, and the conjunctiva covering the edge of the lid is drawn inward, bringing with it the skin covering the outer lid, until the lashes, instead of pointing forwards and a little downwards, as they should, are made to point directly backward upon the eyeball. As a consequence, the eyeball becomes irritated, small abrasions or ulcers appear, superficial inflammation, with thickening of the outer coats of the eyelids, called pannus, follows, and the sight becomes indistinct, light is hardly tolerated, and the eyes weep continually.

If this condition of affairs lasts long, the outer coats of the eye become opaque, or the surface becomes irregular and sight is per manently impaired.

When only a few lashes touch the eyeball, they may be burned out by a needle heated by electricity or an alcohol lamp, or cut out by making an incision on both sides of them as deep as the bulbs and removing them bodily, but the fact must always be borne in mind,

that the lashes in the upper lid especially, are necessary to protect the eye from injury by wind, dust or other foreign objects, and if they are entirely removed, the eye is liable to become dim and dry and sight is apt to suffer. The lashes in the lower lid are evidently intended more for beauty, so that they may be removed quite freely without injury.

The simplest operation to correct a case of slight Entropium, is to excise a piece of the skin with some of the fibres of the orbicular from the outer surface of the lid. To do this, an incision is made, three or four millimetres from the lashes, running the whole length of the lid, or at least farther than the Entropium, then another incision is made on a curved line connecting with the ends of the first, the elliptical piece of skin thus bounded, is then removed with the scissors and the edges of the wound are closed with sutures.

The operation has the best effect if the first incision is made close to the lashes. The amount of skin to be removed, must be estimated by the effect desired.

For the worst cases of Entropium of the upper lid, Arlt's modification of Jaesche's operation, has been done the most frequently. It is done by supporting the eyelid on a horn spatula and then by an incision midway between the eyelashes and the openings of the Meibomian glands, splitting the lid into halves, the anterior half containing the cuticle with the lashes and muscles, the posterior half, the cartilage, Meibomian glands and conjunctiva. An incision is then made on the outside of the lid, about two lines from the lashes and parallel with them; another curved incision is made from one extremity of the second incision to the other, and the elliptical piece of skin is removed with the scissors; the edges of the wound are then brought together by sutures. To make the operation a success the piece of cuticle removed must be so large that the bridge containing the cilia, is really removed from the edge of the lid, leaving a gaping wound to granulate.

It is really an operation to transplant that part of the lid which bears the cilia and carry it farther away from the edge of the lid. When properly executed, the result of this operation is quite good, but it can be well done only once, because the loss of cuticle is so great, that the lid is made much narrower in its vertical diameter. Occasionally some of the transplanted part will slough for want of nutrition, if the bridge is too small, or inflammation will destroy the