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with infected ones, and where the drainage from them does not run through land used by healthy cows. As soon as a cow shows any sign of a contagious disease she should at once be placed in quarantine, and the place where she was before should be thoroughly disinfected. Spraying all walls, ceilings and floors with lime at least twice a year will help to stamp out most of the contagious diseases.

For tuberculosis we test our cows, as it is so far the only way to diagnose the disease, but this test is far from being absolutely reliable, because the condition of a cow at the time of testing will influence her reaction. Of five cows which were condemned from our dairy in 1913, two of the most valuable cows were found without any sign of tuberculosis at the post-mortem examination. Therefore I recommend that cows condemned by the tuberculosis test be isolated and tested again in order to prevent the loss of valuable cows.

Contagious abortion is one of the most dangerous diseases in the dairy herd, and after the disease is once established in one locality it is dif ficult to eradicate it entirely. The cause of contagious abortion is believed to be a germ, transmitted from an animal which has aborted by means of discharging from the vagina, or by a bull that has served an aborted cow. When a cow shows signs of abortion, or has aborted, she should be isolated from the other cows, the place where she has stood should be disinfected with a strong solution of carbolic acid, the stall should be whitewashed, and the aborted calf and all loose litter should be buried deep or burned. The vagina and all parts connected with it should be washed out and the tail and legs kept clean with a solution of corrosive sublimate, one part to one thousand parts of water, as long as any discharge is noticed. A cow which has aborted should not be bred until some weeks after all discharge has ceased, and then she should be washed out before breeding with a solution of corrosive sublimate, but one should see that the solution is lukewarm. The bull should be washed out before and after breeding, so as to insure him from getting infected.

Contagious abortion will develop from common abortion if the latter is not taken care of properly. Poor feed, slippery stalls, deep gutters, crowding on the water tank and hay racks, excitement, offensive odors and so on, are the chief causes of abortion.

Until the outbreak of the foot and mouth disease in the Chicago stock yards recently I had thought that this country was free from the most dreadful disease which can come into a dairy herd, but I have since been informed that this disease was imported in 1902. As I was reared in a country where government authorities have failed to stamp out the disease and have seen thousands of cases, it may be of interest to our institutions to know the symptoms of it so that if a case should make its appearance it could be isolated and dealt with.

The germ of the disease can be carried for miles in all forms of traveling, and an animal exposed will generally develop foot and mouth disease in twenty-four hours. It starts usually with a chill, the animal remains by itself, the back is arched, the hair erect, and there is a shivering of the

muscles. The animal moves with a stiffness and marked lameness. A thick yellowish fluid collects about the inner corner of the eye and the nostrils. Blisters form the size of a pea to the size of a quarter of a dollar about the mouth, the feet and the udder; they contain a watery fluid and soon burst, leaving raw sores, as though a piece were torn out violently. There is constant slavering from the mouth, the saliva becoming thick and ropy. The mouth is often so sore that the animal can not eat solid food. The blisters about the feet often cause shedding the hoofs. The mortality is not high; the greatest loss is in the falling off of flesh, abortion to almost the entire herd and general ruin of the system. Milk from infected cows is very dangerous. Should any of our herds become infected without isolation quarters the whole herd would be ruined.

There are many more diseases which befall a dairy herd, and a cow of great producing qualities is apt to give more trouble than a poor milker. The man in charge of a dairy herd should inspect each animal at least once a day. In this way any sickness in an individual animal or any disorder in the herd may be caught in the first stages and it will be in most cases an easy matter to overcome them, while an animal which is sick for sometime before it is noticed will usually be hard to cure. Keeping the system of the herd in good shape by feeding laxative foods, letting them have free access to salt at all times, and keeping all quarters connected with the dairy thoroughly disinfected will prove a good preventive of diseases.

A salt mixture which we use on our milch cows and pregnant heifers in connection with the treatment for abortion is highly recommended to keep the cows in good condition. It is composed of ten pounds of sulphur, six pounds of copperas, three pounds of saltpetre, three pounds of air slacked lime, one pound of asafetida, mixed with one barrel of common salt. The treatment of milk fever, which frequently occurs in heavy milkers, should be what we call Schmidt's treatment, which means to inject a solution of three drams of iodide of potash dissolved in one quart of clean boiled water into the udder after the milk is drawn out. This treatment has reduced the mortality of milk fever more than one-half.

In closing I want to say that the success of a dairy depends mainly on its management. The dairy man who loves his cows, knows each one, her characteristics and performance, will always see that she is properly cared for, and will easily see any appearance of sickness. The man who loves his cows will not hesitate to lose a night's sleep, when he knows that the life of one of his cows is in danger, and in this way avoid the loss of cows and calves.

The value of milk as a food stuff, and as a diet in diseases of all kinds, in preference to heavy meats is recognized by prominent authorities the world over, and as state institutions are able to produce milk cheaper than any private owner of a large dairy we should be provided with the equipment absolutely necessary to operate our dairies as a highly paying proposition for the benefit of our patients.

*BRAIN HEREDITY.

By H. A. Lindsay, Second Assistant Physician, Independence State
Hospital, Independence, Iowa.

In chemistry symbols were invented to denote the character of substances and the changes which they undergo.

The study of biology is confronted with terms as determinants, traits, possibilities, etc., to denote properties or conditions of germ plasm. Pangens, idioblasts and biophores are the hypothetical units of idioplasm.

Thompson states, "The imaginary pangens or determinants are elements in a notation like the graphic symbols of chemical molecules, and their utility does not depend on any visible reality; their validity is tested by the degree in which they enable us to formulate conceptually what does occur, and to reach forward from this formulation to more precise observation and experiment."'

Professors Yves, Delage and Haeckel indicate that it is not necessary to have such symbols in order to understand the changes in germ plasm, as these changes can be understood without recourse to such measures, and they argue the impossibility of science without imaginative concepts.

The same might be said of chemistry, however, but we are willing to grant that chemical symbols are convenient when we desire to inquire into the nature of substances. The point is that these terms are used in the same sense as chemical terms, and, according to our reasoning, represent chemical and potentially active substances. With this idea before us we can see that the organism of man, unified as it is, is built up of a very large number of independently variable and independently inheritable items.

It is but a short step from this to the thought that these characteristics are constant factors in our makeup, and, as Weisman has put it in his writing relative to the theory of the continuity of the germ plasm, that "in the divisions of the ovum the whole of the germ plasm is not broken up into determinant groups; part of it is kept intact and handed on from cell to cell along a lineage or 'germ track' which may be very short or very long, until, sooner or later, it stamps a cell as a primordial germ cell.''

In other words, while some of the cells derived by division from the fertilized ovum become differentiated as body cells some of the cells retain a quota of intact germ plasm and eventually give rise to recognizable germ cells.

*Read before the Buchanan County Medical Society, December 16, 1914.

Both owe their existence to the germ plasm from which they sprang in the fertilized ovum and are its lineal descendants, but the somatic or body cells are constituted of special segregated and liberated determiners, whereas the germ cells are those or the descendants of those that retain the assemblage of determiners.

To illustrate this speculation let us turn our attention to a visible transformation in the life of the thread worm of the horse. Boveri found that each of the first two segmentation cells receives four chromosomes characteristic of the species. One gives rise to all the body cells, and the other to all the germ cells. In the lineage of the former there is a visible reduction of the chromatin, and in the lineage of the other there is no such visible reduction. This seems to be a very clear example of the "continuity of the germ plasm," and we are now able to get some insight into the "secret of life."

Combining mind and matter and regarding the whole as potentially active chemical compounds we are able to see a little clearer than did Harvey in the fifteenth century when he expressed with such quaint words his bewilderment before the baffling problem of development: "Although it be a known thing that the egge is produced by the cock and the henne, and the chicken out of the egge, yet neither the schools of physicians nor Aristotle's discerning brain have disclosed the manner how the cock and its seed doth mint and coine the chicken out of the egge."

Profound thinkers tell us that there is no secret of life separate from the secret of mind. In other words mind is the result of life.

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Spencer credited his "constitutional units" with much power: "They carry with them the traits of the species and even some of the traits of the ancestors of the species, the traits of the parents and even some of the traits of their immediate ancestors; and the inborn idiosyncrasies of the individual organism itself." They must be in some respects fixed," says he, and in other respects plastic; while there fundamental traits, expressing the structure of the type, must be unchangeable, their superficial traits must admit of modification without much difficulty, and the modified traits expressing reaction in the parents and immediate ancestors, though unstable, must be considered as capable of becoming stable in course of time."

According to this same author, "germ cells are essentially nothing more than vehicles in which are contained small groups of physiological units in a fit state for obeying their proclivity toward the structural arrangement of the species to which they belong."

If we follow this reasoning we are led to the understanding of the inheritance of pathological or retrogressive brain conditions which result in aberrations, or we may see clearly the path of progressive changes resulting in well-balanced minds.

The seal has been set upon the germ plasm in the germ cell and is thus passed down the line. As we cannot see the changes in the brain or other organs of the body we must refer to them in terms as biochemical changes, etc. These changes which are constantly occurring in the body are also common in brain substance, and speaking now of the changes in this latter

organ we may say that the brain cells receive an inheritance from germ cells which in turn receive their inheritance from their ancestors and must carry their potential characteristics from one individual to another.

Meyer Solomon states that,-"The human mind is, at bottom, a single uniform primitive make-up or constitution. Since our phylogeny and ontogeny are the same and since the conflicts with which all men have had to deal have been more or less similar, man has developed a uniform mental constitution, with more or less similar mental trends or psychic tendencies. The predominant tendencies, the proportionate strength of the individual trends and the specific combination or admixture may differ, but the general goals or directions are the same. We all have the same instincts. The same feelings and emotions prompt and guide us, but the proportionate relationship and intensities differ in all of us under different occasions or in each of us at different times or on different occasions. Still, the number of possible instincts, feelings and emotions are the same for all of us, and any of them may, under sufficient cause or provocation, be brought into activity, some more easily, others with greater difficulty." Without further developing Dr. Solomon's ideas we may say that the activities and the conduct of aberrated individuals are but the expressions of tendencies or traits which were always present in the organism and which were brought to the surface when the stimulus was applied, or when the exciting cause, be this typhoid fever, childbirth, adolescence or involution, introduced it.

The only reason we are not all victims of some sort of aberration is that the determiners are potentially active or inactive under the stress, disease, grief, fear, normal physiological changes and accident to which we all are subject. All humanity has a normal tendency toward aberration. In some it is weak, in others strong and in the so-called normal it is dormant. These tendencies may be modified by environment, training, race culture, pedogogy, morality, the cultivation of the will power and by high ideals in practical life. Only the weak fall.

There is nothing mysterious about the causes of insanity if we keep before us this idea of "the continuity of the germ plasm," and we may possibly see quite clearly the modifications which take place in the somatic cells and interpret the part played by organs of the body in stimulating processes which alter temporarily or permanently the cells of the brain which bore the stamp of predisposition. The fertile soil was always there.

To recapitulate, man not only has a uniform primitive mental as well as physical make-up, but also a universal polymorphous perverse psychophysical predisposition or possibility, this predisposition varying in degree and depending for its expression on the relative proportionate, instinctive, inherent constitution and on the life experiences.

Aberrations such as insanities, criminality, moral imbecility, sexual perversion, alcoholism, drug mania, feeble-mindedness, delinquency, prostitution, dependency, hoboism and vagrancy, fanaticism, eccentricity and other conditions are simply the expression of degrees of retrogressive traits present in all of us, and are not so much differences of kind, which is to say that the only difference between a normal and an abnormal individual is the

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