PLATE 1-Grade Shorthorn cow that reacted and continued

to react to the test.

While not in milk she continued in thin

flesh all Summer. Autopsy revealed marked tuberculosis of liver and lungs with tubercles in other regions. A case not cured by the tuberculin, nor one in which the course of the disease was apparently hastened by its use.

PLATE 2-Liver of animal shown in Plate No. 2. White spots represent tubercular areas. Organ much enlarged.

PLATE 3-Lungs of animal shown in Plate No. 2. Large white area represents a section of one lobe, showing a number of tubercular abscesses filled with a cheesy like substance from

broken down tubercles.

Other lobes of the lungs also much

enlarged and filled with tubercles of various sizes.

PLATE 4-A part of the mesentery from specimen in the college museum, showing presence of tubercles scattered over the surface.

PLATE 5-A portion of the omentum from a cow covered with nodules of tuberculosis. ("Grapes.")

EFFECT OF TUBERCULIN ON HEALTHY COWS.

There exists among cattle growers an opposition to the tuberculin test because of a possible injurious effect, especially upon dairy cows. To determine whether or not this is true a series of experiments were made by D. James Law at the Experiment Station at Cornell University at Ithaca, N. Y., in 1894. There was set apart for experimentation two Holstein cows and one Jersey in full flow of milk, being about six weeks after calving, and two dry farrow cows of common stock, one pointing to a Shorthorn ancestry and the other to a Devon. Meanwhile observations on the milk of three other cows, two Holsteins and a Jersey, in full flow of milk afforded a fair comparison between cows treated with tuberculin and others under similar conditions but without such treatment.

The first five cows each received in proportion to its size a full dose of tuberculin weekly.

The tests began October 30th and closed December 13th following.

In summing up his conclusions Dr. Law says:

"There is nothing in the records of temperature that would indicate, either at the time of the test or later, that the tuberculin had proved in any way inimical to the general health. Had the health been impaired by the repeated operation of the tuberculin it might have been expected that the constitutional disturbance would have been more distinctly marked in the later tests than in the earlier ones, and as no such tendency is observable it may be safely concluded that so far as illness can be indicated by a variation of temperature, test doses of tuberculin, in the absence of the bacillus, does not seem to produce any such illness in the healthy animal.

It has been alleged that the repeated use of tuberculin on animals slightly tuberculous abolishes the tendency to reaction under the use of this agent. If this were true it would argue rather a curative than a malific action of the tuberculin, but in other experiments I have found the second test, made a week or more after the first, to produce a no less marked reaction, so that this alleged tolerance need not be taken into account in the cases before us.

MILK RECORD.

"The milk record may be accepted as a more sensitive test of constitutional injury than temperature, breathing or pulse. It is also farther reaching than these other indications, as it