170 STATE BOARD OF AGRICULTURE. 



The salient points l^rought out in these investigations will be submitted as 

 a technical bulletin in the future. 



The investigations on niicrobial decomposition of peat are to be continued 

 under the direction of Dr. Robert M. Snyder. 



Research Associate Cooledge, has profited by his advantage in not Ijeing 

 required to spend any time in the class room or student laboratory as evi- 

 denced by the very satisfactory report of progress which follows : 



During the past year I have continued work upon project Adams 3a, which 

 has the following for its object: 



(a) A study of methods in use at the present time for determining the 

 bacteriological condition of dairy products. 



(b) An attempt to develop new methods where the old are found inade- 

 quate. 



(c) A study of bacteriological problems relating to market milk by means 

 of tests developed under (a). 



Progress made upon this problem has been reported as follows : 



1919-1920. 



The keeping quality of milk as judged by the colorimetric hydrogen-ion 

 determination (L. H. Cooledge and R. W. Wyant), Journal of Dairy Science, 

 Vol. Ill, No. 2, March, 1920, Michigan Academy of Science, March, 1920; 

 Local Section of American Chemical Society, April 1920; Local Section of 

 Society of American Bacteriologists, December, 1920. 



An improved comparator, Journal of Lidustrial and Engineering Chem- 

 istry, Vol. 12, No. 5, May, 1920. 



1920-1921. 



Judging the keeping quality of milk by a pH method, laboratory section 

 American Public Health Association at San Francisco, California, Sept. 15, 

 1920. In American Journal of Public Health, December, 1920. 



A new laboratory method of determining the condition of milk. Michigan 

 Public Health Association, Bay City, May 26, 1921. 



The two following papers covering work completed during the past year 

 have been completed and are ready to submit for publication: 



The colorimetric hydrogen-ion determination as a means of studying bio- 

 logical changes in dairy products, and 



An experiment in improving the milk supply of a city milk plant. By L, 

 H. Cooledge, Bacteriological section and 0. T. Goodwin, Dairy section. _ 



Problems which I have under way are progressing favorably and give 

 promise of very interesting results. 



[L. H. Cooledge.] 



The bovine infectious abortion project (Adams, 3b) has continued under 

 the aggressive leadership of Research Associate Huddleson, during the year. 

 Very satisfactory progress on this vital problem is indicated l^y the following 

 report : 



During the past year my time has been largely occupied with the prol)lcm 

 in bovine infectious abortion. Additional work has consisted of teaching 

 (Bacteriology 19), examining blood samples (bovine origin) for bovine infec- 

 tious abortion and bacteriological examination of material from l)oth animal 

 and human origin. 



One trip was made during the year to Coldwater, Michigan, for the pur- 



