Rabbit No. 14, inoculated with material from rabbit No. 7. Rabbit No. 15, inoculated with material from rabbit No. 7. Rabbit No. 16, inoculated with material from rabbit No. 11. These rabbits, Nos. 14, 15 and 16, are still under observation, and it is hoped that it will be possible to obtain, from further experiment, material of the greatest possible virulence for use in investigations in connection with certain phases of this work. In all experiments the emulsion of the brain or cord used for subdural inoculation was examined for the presence of micro-organisms by making cultures. In no case has contamination been detected. Daily temperature observations are made in every instance, and these and other records preserved in an envelope bearing the number of the animals, etc. All of these observations have been carried on in collaboration with the St. Paul board of health bacteriological laboratory. The cases there observed will be reported elsewhere. It is here fitting to express the thanks of this laboratory to Drs. Rothrock and Price for their courtesy and for the materials and data placed at its disposal. THE BACTERIOLOGICAL EXAMINATION OF WATER. Very little could be attempted in the matter of the bacteriological examination of water, although the necessity of such work is very apparent. Some few partial examinations of the water supplied to the laboratory by the city pipes were made, but nothing further was to be observed than that the number of bacteria per c. c. was comparatively small, during May and June varying from 40 to 200 colonies. On one occasion B. coli communis was found. Several examinations were made, at the request of the Owatonna public school management, in the search for B. diphtheriae, which resulted negatively, as previously stated. The method usually employed in this search for B. diphtheriae, which may have been faulty, was as follows: To about 100 c. c. of the sample of water about 400 c. c. of a sterile one per cent dextrose broth was added, and the whole incubated for twenty-four hours, when Löffler's serum mixture tubes were ir oculated, and agar and gelatine plates made. The original and all subcultures were carefully examined for B. diphtheriae, but in no case was it, or any bacillus closely resembling it, found. BACTERIOLOGICAL INVESTIGATION IN HOG CHOLERA AND SWINE PLAGUE. Only one series of investigations has been undertaken, which has unfortunately ended without result. No demand has arisen for investigation, except in the one instance, when the materials, improperly directed and without any information as to their character, or what was desired in regard to them, were received. The name of the sender and other information reached the laboratory only when, through the growth of putrefactive micro-organisms, the examination was rendered doubly difficult. Neither the bacillus of hog cholera nor of swine plague was to be found in the material examined (lungs, colon, spleen, stomach, liver), although B. coli communis and B. pyocyaneus were found. The sender was immediately noti fied, as soon as his address could be obtained, and he was invited to send further specimens from other cases. Full directions were given, but no reply was ever received to this communication. The progress of these diseases in neighboring states, and according to reports* in this state also, seems to demand the active cooperation of all interested. Many points in which bacteriological examinations may aid the clinician will doubtless suggest themselves, and not the least conspicuous would be the determination of what percentage of cases occurring are hog cholera, what swine plague, and how many are cases of mixed infection. While this laboratory is not at present in a position to publish results of scientific investigation, it would seemingly be wise to make some announcement in regard to what work the laboratory is prepared to do, and what is expected of those who desire to avail themselves of its services. The following circular of information, which has been prepared with this object in view, is therefore submitted for the approval of the board: F. F. WESBROOK, M. D. *See report of superintendent of Farmers' Institutes, for 1896. Director. Office of State Board of Health and Vital Statistics, To His Excellency David M. Clough, Governor, Sir: The state board of health herewith respectfully submits its report for the twenty-sixth and twenty-seventh years of its exist ence, embracing the time from Dec. 31, 1896, to Dec. 31, 1898. HENRY M. BRACKEN, M. D., Secretary and Executive Officer. |