No. 410 was but slightly affected by the inoculation with the germ, and on December 9 appeared to have entirely recovered.

No. 411 on December 9, on the contrary, was very sick from the inoculation with the germ, had been down unable to rise since December 7, and finally died December 22, two weeks after the checks. The autopsy by Dr. Smith was as follows:

The animal was greatly emaciated, weight only 28 pounds. There was an enlargement of both knee and hock joints, but the disease appeared to be confined to the joints only. Lungs show no inflammation or hepatization. Right heart filled with large dark clot, left with larger partially washed clot. Gall bladder distended with very thick bile holding large quantities of solid in suspension. Liver more firm than normal. Stomach contracted; contained very small quantity of viscid bile-stained liquid. Spleen not enlarged; pulp rather dark. Kidneys rather small; on section show fatty degeneration. Two rabbits inoculated with virus from the knee joint, dead in twenty-four hours, autopsy showing death from swine plague; cover-glass preparations from spleen and liver showing swine-plague germs.

The results of the experiment were, therefore, both checks dead. One treated animal lived two weeks longer than the checks, the other treated animal recovered. A saving of 50 per cent in the treated animals against an entire loss of checks, thus showing the possibility of practically treating this disease.

II. In the case of the second experiment, conducted upon hogs for swine plague, the exposure with the germ was not sufficiently severe to kill even the check animals, consequently no conclusions could be drawn as to the value of the treatment. It is probable, however, that the disease of swine plague in hogs can be practically treated. Exposure of an animal that had recovered from swine plague to hog cholera. On December 30, 1890, pig No. 410, that had recovered from swine plague, was inoculated in the vein with 4 cubic centimeters of hog-cholera culture one day old, together with checks and a number of other animals, that had been already inoculated several times with the germ by Dr. Smith.

On January 1, 1891, the animal No. 410 was very sick, but on the 5th and 6th seemed to be improving. On February 10 it was very thin and sore, smaller than when inoculated, and finally died on February 20. The autopsy by Dr. Kilborne was as follows:

Lungs normal.

tricle small clot.

Right side of heart distended with large clot of blood; in left venLiver capsule marked by numerous bluish-white patches onethird to three-fourths centimeter across. On section liver was firm, feeling gritty under the knife. Cortex of kidneys was pale and thickened; other organs apparently normal.

The checks had died on January 1, two days after the inoculation, with the germ. The swine-plague animal thus showed considerable resistance to the disease. This animal was treated at the same time as a number of animals by Dr. Smith and must be considered at the same time and in connection with them.

IS IMMUNITY FROM HOG CHOLERA HEREDITARY?

A pair of guinea-pigs which had been rendered immune to hog cholera in August, 1890, were carefully kept apart from other animals for a number of months. The offspring (which it may be noted did not grow rapidly for the first month) were when three months old inoculated with one-tenth cubic centimeter hog-cholera culture one day old, together with two checks. The checks, which were a little smaller and younger than the other animals, died seven and twelve days after the inoculation. The other animals died fourteen days after the inoculation.

The autopsies upon the latter two were as follows:

No. 1. At the point of inoculation subcutaneous tissue indurated over area 1 inch in diameter, the superficial layer of abdominal muscle being involved. Follicles in cæcum infiltrated with a grayish substance. Peyer's patches swollen, pigmented. Liver deeply reddened and sprinkled over surface with minute grayish areas. Cover-glass shows hog-cholera germs. Spleen apparently normal. Blood vessels of kidneys much injected.

No. 2. Inguinal glands enlarged and reddened. On the left side at the seat of inoculation a cheesy tumor "2 by 4," the surrounding tissue having a blue-black color. Immediately under the peritoneum along the dorsum a number of tuberclelike bodies. Abdominal cavity contains 1 cubic centimeter of clear yellowish serum. A white opaque exudate was spread over liver and spleen. Lungs emphysematous, the surface sprinkled with translucent dark dots. Cover-glass from liver showed few hog-cholera germs.

Thus is proved that the offspring from immune guinea-pigs in the case of hog cholera are not themselves immune.

GLANDERS.

A study of the chemical products in cultures of the glanders germ has been begun. At this writing a non-poisonous albumose has been extracted, but only traces of a ptomaine-like body have been obtained. It is probable that in the case of this germ an albumose is the principal and practically only product.

Experiments are being conducted with the purpose of seeing if animals can perhaps be rendered immune to glanders by a manner of treatment similar to that adopted in the case of hog cholera and swine plague.

MISCELLANEOUS.

In addition to the study in connection with the diseases just recorded the writer has given some little attention to the presence of tyrotoxicon in milk and cheese. In May, a sample of milk from Maryland came into his hands which was supposed to have caused the sickness of a number of children. The symptoms as given indicated a possible tyrotoxicon poisoning. The milk was examined for the poison, but the latter could not be detected. Some months after this, cheese, which had produced sickness in this city, and two lots which had caused illness in Ohio, were received. In all three cases the questionable tyrotoxicon was blamed for the sickness. I could not, however, establish the presence of tyrotoxicon in any instance by the methods prescribed by Vaughan. This led me to repeat one of Vaughan's experiments, which should have given me considerable quantities of tyrotoxicon. A half gallon of fresh normal milk was placed in a loosely stoppered glass jar and allowed to stand at the temperature of the room for three months during the summer. At the end of this time it was examined for tyrotoxicon, but the test failed to establish its presence. From this milk as well as from the samples of cheese Dr. Moore isolated several different germs, but other more important work has prevented a closer study of these and their products.

Our own experiments, supported by the negative results of a number of other chemists, force us to conclude that the toxic principle of poisonous cheese and milk has not been yet sufficiently studied, and that there is here a very important field for further investigations.

A number of other unimportant examinations and analyses have been made, but the facts established in regard to hog cholera and swine plague are the important results of our work.

Tabulated results of experiments in producing immunity from hog cholera in

Experiments in producing immunity from swine plague in guinea-pigs.

REPORT OF THE UNITED STATES BOARD OF INQUIRY CONCERNING EPIDEMIC DISEASES AMONG SWINE.

Hon. J. M. RUSK,

Secretary of Agriculture:

SIR: The above-named Commission received appointment from the Department of Agriculture during the month of December last, and their formal notification thereof was accompanied by a letter of instructions similar to the following:

U. S. DEPARTMENT OF AGRICULTURE,

COMMISSIONER'S OFFICE, Washington, D. C., November 27, 1888.

SIR: I inclose with this an appointment for you as a member of a Board of Inquiry, the other two members of which are Prof. William H. Welch, of Johns Hopkins University, and Prof. T. J. Burrill, of the University of Illinois. The Board will convene at the Department of Agriculture, Washington, D. C., on December 12, and decide upon the plan of investigation and the methods to be employed. The details of this investigation will be left to the Board, without instructions or interference on the part of the Department, but all the facilities of the Department will be placed at its disposal.

I desire that the investigations of the Board will determine the following points: (1) If the diseases of swine investigated by the Bureau of Animal Industry were properly described in the reports for 1885, 1886, and 1887, and if they were caused by the germs mentioned in connection with them, and if these germs were properly described.

(2) To what extent were these descriptions of the germs original, and to what extent had they been antedated by other correct descriptions and by investigations which would demonstrate their etiological relation to the diseases of swine, and particularly to the diseases as they exist in the United States.

(3) Is the disease which has been investigated by Drs. Billings and Roberts, in Nebraska, identical with one of the diseases described by the Bureau of Animal Industry, or is it different from both of them? Are their descriptions of the disease and the germ correct? Do their investigations show that the conclusions as given in the Bureau report are incorrect? Have any facts been established in regard to the swine diseases of this country by these investigations which differ materially from the conclusions given in the reports of the Bureau of Animal Industry?

(4) To what extent is Dr. Detmers justified in his assertion that "Dr. Salmon's Bacterium Suis, discovered by him in 1885, as a substitute for his micrococcus, has nothing whatever to do with swine plague. It is a septic germ, readily kills rabbits (cf. Bulletin of the Ohio Agricultural Experiment Station), and causes septicemia, but has no connection with the disease in question?" Has Dr. Detmers published the details of any investigations which demonstrate the etiological connection of any microbe with an infectious disease? If so, does the microbe he has discovered differ specifically from both of those described in the Reports of the Bureau of Animal Industry?

Please make such suggestions as may occur to you in the course of your investigations in regard to the proper method of treating and preventing these diseases. The report of the Board should be submitted to me on or before April 1, 1889.

Very respectfully,

Dr. E. O. SHAKESPEARE,

1336 Spruce street, Philadelphia, Pa.

H. Mis. 270-9

NORMAN J. COLMAN, Commissioner of Agriculture.

129

(NOTE. Professor Welch declined, and Prof. B. Meade Bolton, of the University of South Carolina, was appointed in his stead.) Modifications of the letter of instructions were made with one member of the Commission, viz, Professor Burrill, before his acceptance of his appointment; but as these were not made with the other members, they are not here inserted.

In fulfillment of the object of their commission, as explained by the accompanying instructions, the Commissioners met at Washington during the week of last Christmas and organized by the election of Dr. Shakespeare as chairman, and Prof. B. Meade Bolton as secretary. They sketched out a plan of work as follows:

(1) Examine methods of observation and research pursued in the Bureau of Animal Industry at Washington.

(2) Examine diseased hogs furnished by the Bureau of Animal Industry, making special endeavor to find the two diseases described by the Bureau authorities and the two germs claimed by them to be the cause of the respective maladies.

(3) Visit South Carolina for the purpose of examining into the nature and cause of epidemic diseases among hogs prevalent there. (4) Visit Nebraska for the purpose of examining the methods of Dr. Billings and the disease upon which he was at work.

(5) Examine into nature and cause of disease among hogs in various localities in that State.

(6) Visit as many outbreaks of swine disease in different parts of the country as possible with a view of finding if such existed-the two diseases and the two germs described by the Bureau authorities. (7) Visit Dr. Detmers to examine his claims of priority and his methods of investigation.

(8) Examine separately and individually the morphological and pathogenic qualities of the germs found in the various localities where the Commission might find epidemics prevalent among hogs.

(9) Examine the question of immunity after a natural attack and after artificial inoculation from the standpoint of experience in Nebraska.

(10) Test especially the question of artificial immunity by experimentation at Philadelphia upon inoculated and recovered pigs obtained in Nebraska, as compared with controls.

After a session in Washington of several days, during which the first and second objects above mentioned were carried out, the Commission proceeded to Columbia, S. C., where they arrived January 1, 1889. They found and examined two outbreaks in the immediate vicinity of Columbia, and one other some 80 miles distant therefrom, viz, near the village of Florence, in the same State. The disease found in that State presented the clinical features and anatomical lesions, as well as germs, of "hog cholera," the latter, however, associated with some other microbes.

The Commission next proceeded to Lincoln, Nebr., and were cordially received by Dr. Billings, who rendered every facility for the prosecution of their inquiries. His methods were examined, and some five or six hogs which had been previously inoculated by him were studied post-mortem and bacteriologically. The lesions found were in the main corresponding to "hog cholera," as previously described by him under the name of "swine plague," and also noted by the authorities of the Bureau of Animal Industry as "hog cholera." Specimens were also obtained from a natural outbreak located some nine miles away, with lesions and germs apparently