EXPERIMENT STATION REPORTS. 



255 



from the milk plants which supply the city of Lansing. These analyses 

 were made by Mr. R. W. Wyant in connection with a sanitary inspection 

 of the plants, which were scored by Mr. L. H. Cooledge. The table below 

 gives the details of the scoring and the count. 



Of these 16 samples, 81.2 per cent Avere grossly contaminated with sur- 

 face washings or sewage or in some cases both. The average bacterial 

 count of all samples was over 800 per c. c. with a minimum count of 4 

 and a maximum count of 116,200 per c. c. Fifty per cent of these sam- 

 ples would pass unquestioned from the standpoint of counts only. The 

 prevailing comparatively low counts in the water supplies of Lansing's 

 city milk plants without doubt may be attributed to the deep wells 

 necessitated by the geological formation in this vicinity. 



*Two wells. 



The bacterial count of the agar plates, which are incubated at 37°C. 

 indicates the number of bacteria in each c.c. of the water which may 

 be of intestional origin or related forms. 



The gelatin plate count gives the number of bacteria present which 

 grow at lower temperatures and are for the most part soil or natural 

 water organisms. 



Gas and acid in the agar shakes indicate that there is at least one 

 organism of the colon group present in 100 c.c. of the water. 



Litmus lactose bile inhibits the growth of most bacteria not of the 

 colon group; therefore growth in this medium suggests serious pollu- 

 tion. 



The above table shows that only four plants out of the 16 examined 

 score above 50. Plants scoring less than 50 should not be allowed to 

 sell milk. In many cases carelessness was the cause of the low score. 

 A general clean-up inside and outside of the building would, in most 

 cases put the score up to 50 with little or no additional cost. The 

 most noticeable feature of the above survey is the fact that 11 out of 

 the 16 plants score undei* 50. (L. H. Cooledge.) 



Mr. C. W. Brown has devoted approximately one-half of his time to 

 Adams project lb and the remainder to studies in the broad field offered 



