this condition, yet so far I have not heard anything in regard to the application of the wire gauze splint. While the plaster of Paris cast is very efficient, and in some cases it would not be well to dispense with it, yet in the majority of cases a galvanized wire gauze splint will be found to be strong and very efficient in cases of fracture. It is applicable to most cases. It is light and airy, and it is a form of splint that should be used more frequently than it is. It is admirably suited for injuries of the ankle joint. An angular splint can be made out of this material. The galvanized wire can be soldered and the margins can be cut with scissors and hemmed over with pieces of plaster, which make it a comfortable, light and strong splint.

Dr. E. R. Lewis (closing): The first speaker, Dr. Jay of Chicago, compels me to say, from what I have found out with regard to ununited fractures, that many of us are yet clinging to December, while the earth is in her June. The pathology of this affection has been revolutionized since we studied medicine. We all know to-day that the periosteum is not the osteogenetic factor in the repair of bone. It has been proven conclusively that it is not. The experiments of Mr. Macewan of Glasgow established that beyond the possibility of doubt, and no longer do we talk of repair of bone through periosteal tissue. If you remove a bone for one inch or two inches and preserve the entire periosteum throughout, it collapses and forms a fibrous tube and does not develop a single osteoblast. That has been proven, and we must recognize it because it is a fact. What is it that produces and repairs bone? It is the soft tissue which resides within the bone itself. There is where the osteoblast is developed; there is where the bone receives its repair. The periosteum is not only a protection, but it is the nidus through which the circulation reaches the bone tissue proper. It is aboslutely necessary to the protection of the bone and allows vessels. to reach the bone, but it does not enter in as an osteoblastic factor, and we must recognize that point before we can intelligently discuss delayed union, non-union, or whatever other term you may wish to apply to those cases which do not unite within a certain length of time. We must discard the old idea.

Dr. Crook's case of ununited femur, that he

speaks of as having occurred in California, is interesting. I reported cases at the Chicago meeting where I had wired the humerus, the ulna and three months after the wires had been applied with soft parts uniting perfectly throughout, the bone was not repaired, due to specific influences which we have not discussed in this paper to-day, but which were dwelt upon at length in the paper I presented in Chicago.

Dr. Thorn has made a very happy suggestion relative to the starvation of these tissues and speaks of loose dressings and also calls attention to the fixation of joints. There is one point that we must understand more thoroughly and that is, to fix a leg from the sole of the foot to the hip. We can no longer hold to those ideas, which we believed were as sacred as the Holy Writ itself, because experience has taught us to the contrary. We are advancing, and we must not be clinging to wrong ideas.

I am sorry that Dr. Hoy did not hear my paper. He spoke entirely of the treatment of ununited fractures and illustrated it with six holes bored by a jeweler into the bone, and it served a good purpose. Why did the boring of these holes produce repair? I remember twenty-five years ago when the late Professor Pancoast of Philadelphia exhibited a woman from the far West, as he called it at that timeWisconsin-who had an ununited fracture of the tibia. The bones were fixed together by means of screws. How did they act? He opened up the bone tissue through which the osteoblasts were formed, and from which the genuine bone structure began. The six holes drilled by the jeweler opened up the cancellous structure of the bone, where the soft tissues in the bone itself produced osteoblasts, without producing bony union. Had he not used a plate at all, the bone would have been more rapidly repaired and better.

Dr. P. Daugherty: Speaking of treatment, I do not care to enter into the subject after Dr. Lewis has practically closed the discussion, except to say that from my own personal experience I reported more than half a dozen cases at the Chicago meeting. I prefer the ivory pegs to the wire because they are absorbed. The ivory enters into the formation of bone by absorption.

A word in regard to Dr. Howard's case of

united radius, after three years. If we break loose the fibrous tissue at the ends of these bones and open up the cancellous structure, union will take place. You expose the boneproducing membrane by so doing. And if I know that I have a case of delayed union, I chloroform my patient and violently rub the ends together in order to knock off the fibrous tissue which has formed a false joint, as we term it.

COLOR BLINDNESS.*

BY D. EMMETT WELSH, M. D., GRAND RAPIDS, MICH,

The object of this paper is not to enter into a theoretical consideration of color blindness, but to present for your consideration the importance of examinations for its detection in the train service of the railroads. Last year you listened to an able discussion of this subject by Dr. Wescott of Chicago, and also witnessed the practical tests as presented by Dr. Williams, now of Boston, formerly connected with the C. B. & Q. Incidentally I might mention that to Dr. B. Joy Jeffries of Boston, Mass., belongs the credit of first bringing before the railway managements of this country the importance of these examinations, not only from a theoretical standpoint, but its practical utility.

Various roads have adopted different forms of examination for the color sense, yet in the main they vary only slightly in the methods employed.

I will consider the subject of color blindness only in connection with normal eyes. In the adoption of these examinations by a railway a great difficulty confronting both the employer and employe is skepticism, and this is a feature that must be overcome. The employe imagines it is a good device to get rid of him when his record is good. The management, considering the welfare of the traveling public, does not appreciate its importance, and therefore considers that to distinguish between red and green is all that is necessary, until brought

to witness an examination in which the defect is prominent. The only satisfactory manner, both to the employer and employe, *Read at the ninth annual meeting of the National Association of Railway Surgeons, at St. Louis, Mo., May, 1896.

in which these examinations can be made is by the ophthalmologist. He is unbiased in his views, and will render a report in accordance with what is found, whereas a foreman or assistant superintendent, having an enmity, can easily, by the examination he makes, cause the applicant to commit error and thus relieve him from the service without good cause.

Two conditions should always be borne in mind in making these examinations, viz.: Mental capability and real defect of color sense. Many men have a feeble color sense, and colors similar in character fail to impress the applicant as really different; in other words, hesitancy is displayed where positiveness should exist.

If a true defect is found, further examination is not necessary. Man, in the various walks of life, selects that which is pleasing and enjoyable to him, and profitable, but after a time so many things bearing upon the same subject present themselves that unconsciously he falls into a certain "rut" and becomes automatic. This is nowhere better illustrated than in the mechanic or engineer. In the latter, from years of trial as a fireman, the location of signal tower and station is known, and even on the darkest night something either marked or vague tells him "where he is at."

A few years of experience teaches the engineer where to apply the air to stop at station or water plug; the condition of the track tells him his location, and if the sense in this direction is quickened, then his perceptive sense must be quickened. A comparison as to intensity of light informs him its character, and though the judgment may be defective, he judges unconsciously, and is always on the alert for the slightest variation.

We, as surgeons, are all familiar with the fact that the engineer can very readily detect the slightest variation of sound while running, and can easily locate a defect in his machinery and readily perceive locations and light. Yet withal it is by comparison, and the slightest variation from the usual position of a signal might produce terrible destruction of life if the engineer was unable to detect differences

in color.

I make examinations for visual defects and color blindness for the following roads: Grand Rapids & Indiana, Chicago & West

My form of examination is as follows: The applicant presents himself with a card from the superintendent of the division to which he belongs requesting an examination.

I test the distant vision by Snellen's test, and new employes must have normal vision. If the examination of old employes shows one eye normal and the other one-half normal, a certificate is issued.

I then use Holmgren's method for the color test, and if the applicant is able to pass the same the examination is practically complete.

Thompson's method, varying slightly from this, I use as a second test, and on finding all correct I dismiss the applicant and sign a certificate, sending a report to the superintendent, who sends the same to our chief, Dr. G. K. Johnson, who indorses the report.

If an applicant fails in this and then cannot realize his defect, I examine him by the following device, arranged at my office: I have a caboose end built in a recess for that purpose. I have at the top and at each side and on the platform a lantern; these are the same as those in use on the rear ends of trains on the various roads. Colored glass is placed in them, behind which are electric lights of the same luminosity. The candidate is placed 30 feet away and asked to name the light as flashed. In every instance of color blindness errors in distinguishing the right colors are shown as with Holmgren's test.

This form of examination is done with a view to prove the correctness of Holmgren's test, and also to convince the skeptic that error does exist and its proof is palpable.

..1,380

I have examined 1,380 men, including engineers, firemen, brakemen, conductors and switchmen, with the result indicated below: Whole number examined.. Number defective in vision or color sense Number having defective vision........ Number having defective color sense.. Percentage having color defect....... 2.53 Percentage having visual defect..... 4.49

97 62

35

DISCUSSION OF DR. WELSH'S PAPER. Dr. W. S. Hoy, Wellston, Ohio: A great many railroad surgeons are required to make examinations for color blindness among employes, and everyone who makes these examinations must be impressed with the dirty,

my duty to examine the men on the C., H. & D. system as far down as Ohio, and having examined a large number of sectionmen and trainmen, I found a number of persons in the employ of the company who were old and trusted employes, who had been on the road for years, and had never had an accident befall them. In two instances which I remember at this time, when Thomson's test was presented, the men had no means of knowing red from yellow, or blue from green. If I put out a red color they would be apt to call it blue or green, and they were just as apt to call it rose as any other color. After having failed on Thomson's test with skeins of yarn, I found that these men could go into the yard at night and designate promptly the lantern signals. While on the subject of color blindness, it has been said in the paper that some trainmen have difficulty in hearing. This is true. I have known men, standing the eye test, who could scarcely hear a watch tick at twelve inches, six inches, or even four inches, and who when the engine was blowing could hear an ordinary conversation. There seems to be some circumstance connected with the life of the engineer on a train which enables him to perceive by sound. What do we mean by color blindness? We mean inability of the individual to differentiate certain colors presented to him, and which are used on railroad trains for signals. We all know that if we were traveling on a train, we would feel more secure did we realize the fact that the trainmen, the sectionmen and stationmen, had an accurate idea and conception of the various colors presented, especially at night. Strange as it may seem, some of the old and trusted employes of the railroad companies of this country have run trains for many years without having met with any accident or without having been the cause of loss of life to the traveling public. I say these things things are strange, and we have great hesitancy in reporting to the company a man who cannot stand the required test. As surgeon of the C., H. & D. system I think there is a great deal in connection with color blindness that we ought to overlook. A great many men cannot differentiate between colors. While they may pick out the fundamental color they cannot select the shades of the color.

I have interviewed a number of engineers en our road concerning the difference in seeing between the electric headlight and the old-time lightning bug headlight, and they tell me while behind the light, going away they can see a long distance before them, but at the approach of the train with the electric headlight, they are not able under any circumstances to regulate or calculate the distance of the engine with the electric light away from them. They cannot tell whether they are 600 or 800 yards distant. I have made a special inquiry about this matter and have found that the majority of engineers do not like the present system of electric headlights.

Dr. C. D. Wescott, Chicago: I quite approve of nearly everything that Dr. Welsh has said, particularly the statement that the examinations should be conducted by an ophthalmologist rather than by a foreman or superintendent. I also believe that examinations for vision and color blindness should be repeated at least as often as once in five years. We all know that vision fails and that certain forms of nervous disease may bring on changes in the color sense.

It is true that some railroad men may fail with the Holmgren or other office tests, but may succeed in differentiating perfectly on the tracks, or when examined by lanterns in the way that Dr. Welsh has suggested. I therefore believe that these tests should always be made as practical as possible; be made to embody as closely as can be the actual experience of men on the train and on the track; in other words, no matter how carefully and thoroughly the Holmgren or Thomson test may be carried out, the test with the colored lanterns should be added and the circumstances should imitate as closely as possible the conditions on the road.

It is very perplexing to know what to do about cases of partial color blindness. partially color blind myself and can appreciate very well the condition of trainmen who can under ordinary circumstances recognize without difficulty the different lights, but who are at a great loss in a foggy or smoky atmosphere. In driving along a country road, a person with perfect color sense will see red cherries on a tree long before an individual like myself. My own wife has poorer vision for form than I have, but her color perception is perfect.

She can recognize cherries on a tree at twice the distance at which I can perceive them. In a clear atmosphere I can distinguish colored lights on the track very well, but in a smoky or foggy atmosphere I am in great doubt. These are the puzzling cases, but as only four per cent. of the men we examine are defective in color sense, we work no great hardship if we reject them all. The argument is often raised, that we should not reject a man with defective color sense who has done good service for the road which employs him for twenty or twenty-five years, and perhaps has never had an accident during all that time. It is considered a hardship to dismiss such a Nevertheless, we should not have men with defective color sense in the train service.

man.

At our last meeting you will remember that Dr. Williams exhibited an apparatus for carrying out color tests with colored lights. It does not imitate as closely the conditions on the track as the method of Dr. Welsh, but it is capable of more modification, and a greater number of different colored glasses can be brought in front of the light than by any other method with which I am familiar. If we could adopt a standard all over the country for these examinations it would be very desirable. It is proper for this association to work in that direction.

Dr. Hoy: Why is it the percentage of color blind females is much less than males?

Dr. Wescott: Because it is a matter largely of education. As a rule, the females are more familiar with colors and work with them more than do men, and it is a matter of education, and perhaps of heredity.

Dr. Hoy: Do you believe the eye can be educated to overcome color blindness?

Dr. Wescott: Possibly, through certain channels. I believe many cases of partial color blindness can be overcome or improved by education. In some cases a defective color sense seems to be psychic rather than organic. Dr. H. M. Bannister of Chicago has written an interesting paper on "Color Blindness as a Psychic Affection." It would be interesting. to every railway surgeon, I am sure.

Dr. W. B. Outten, St. Louis: I will grant that the oculists are absolutely correct from a scientific point of view with regard to color sense, and were I an oculist I should doubtless hold the same views. However, I main

tain that in the running of a locomotive, that so far as the engineer is concerned, there is not an element with which he is surrounded and connected but what he is thoroughly educated and trained. Every nerve he possesses is well trained. There is not an engineer who runs an engine but what has his method of running it, and his plan is carried out year after year irrespective of his color sense. He is thoroughly familiar with the roadbed, the curves, the up and down grades of the track over which he runs. To illustrate what Dr. Hoy said, that in order to test the hearing a watch should be held eight feet from the ear. Look at the utter absurdity of this proposition. The tick of watches is entirely different. If it were possible to have a uniform tick made according to a given rule, we would have a standard to go by. Irrespective of that, amid the roar of steam and rattle of the train the engineer has an ear which is thoroughly educated as regards noises, and he is more competent to hear the click of a defective piece of machinery than any of you or I. The senses of the engineer are acute and active. He has to watch a number of things in front of his engine. He has got to hear and see. I can show you men who cannot tell red from green, yet they are capable, careful, cautious engineers. Take a train going at the rate of sixty miles an hour and the engineer may not be able to tell whether he sees a red light or not, but we consider the brains of the individual. It seems absolutely cruel to dismiss a man who is thoroughly competent in every way except in this one particular, that he has defective color sense. The other senses of engineers are educated to the highest point. Defective color sense alone should not condemn a man and result in his rejection as an engineer, after he has done good and efficient work for the road that employed him.

Dr. Welsh (closing): I am glad my paper has elicited some discussion. Dr. Hoy has spoken in regard to the matter of testing the hearing. I did not mention this in my paper, having left it out entirely. We find a great many engineers who have very acute hearing, while others are defective in this regard. Sounds and noises which are mild and pleasing to engineers would be painful to those possessing normal hearing.

With regard to color blindness, the applicant is not required to make mention of the color presented. No name is asked of him. of the color shown. For instance, a lot of yarns are thrown on a white piece of muslin, in a good light; one test color is selected, and the applicant is asked to pick out colors lighter or darker, or any shade of that color. question of naming the color does not enter into the examination at all. Difficulty will arise in the selection of the colors.

The

A point referred to by Dr. Outten is well illustrated in two cases in which examinations were made by myself, namely, that dependence is placed upon the engineer, or the fireman, and vice versa. To illustrate: One of the younger engineers in age, who has been running a locomotive for fifteen or sixteen years on the Chicago & West Michigan Railroad, and considered one of the best men on the road, and is given fast trains and specials to run, and carries the superintendents and general managers from point to point, one night in going into a station mistook the color and ran into an open switch. A red light was turned on him, and just as they were going around a curve the fireman was doing something on the inside of the cab and did not perceive the color. This was not known, and when an examination was made by the superintendent the color was given as white. The claim was made that in passing over the switch it jumped and threw them off the track. This engineer was sent up for examination along with other engineers and firemen, and when a regular examination was made it was found that he was color blind. He could not tell red, could not tell green, he was red-green blind. His fireman had defective vision, that is, vision was equivalent to about 1-10 normal vision. I made a report to the superintendent of the division and he was laid off with the request to go home and study all colors and come back for re-examination. This was done, and at the end of a month he failed in this examination. He returned in six weeks to two months again and failed again. I have examined him at various times since then until the present, covering now a period of some three years, and at each examination he makes the same error. It has since been learned by the officials and by a statement made by the fireman and engineer, that the fireman