BACTERIOLOGICAL STUDIES OF MILK SUPPLIES 167 



represent the kind of milk they will have in the evening of the day the milk is 

 deUvered, if the milk is filthy when deUvered. It is fair to state, however, that 

 the increase between the five- and twelve-hour plating was partly influenced 

 by the fact that the mean room temperature on this day was 23 degrees C. — slightly 

 higher (1-4 degrees) than the mean room temperature of the days on which pre- 

 ceding and succeeding samples were examined. 



Sample No. 27. Producer No. 14. This is from a licensed dairy. The 

 sample was received October 8, five hours after milking, when the bacterial 

 count was 8,750. After seven hours (that is, twelve hours after milking) on ice 

 there was a slight decrease in the bacterial count, while at room temperature the 

 covmt was only 35,060. The butter fat was 3 . 6 per cent. 



Sample No. 28. Producer No. 6. This is from a licensed dairy, being from 

 the same dairy as No. 25. This was received October 15, five hours after milk- 

 ing. The bacterial count was 227,300. Kept on ice, at the end of twelve hours 

 after milking, or only seven hours after the first examination, the germs increased 

 to 793,000 per cubic centimeter, and at room temperature to 20,970,000 germs. 

 The butter fat was 3 . i per cent. The mean room temperature on that day was 

 20 degrees C. This was at a time of year (October 15) when most people 

 were doing without ice, so we may assimie that this is the kind of milk the cus- 

 tomers of this dairy used for the evening meal. This sample was obtained from 

 the central milk depot and rushed to the laboratory, so it was probably kept 

 under the best conditions which that dairy affords — at least it was not subjected 

 to the dust and the possible heating of a long milk route. 



Sample No. 29. Producer No. 8. This is from a licensed dairy (same as 

 No. 12, First Preliminary Report) and was received October 17. When examined, 

 six hours after milking, the count showed 55,020 germs. At the end of another 

 five hoiurs on ice this did not increase, but at room temperature (mean 16 degrees 

 C.) it reached 124,700. The butter fat was 3 . 3 per cent. 



Sample No. 30. Producer No. 15. This is from a licensed dairy and was 

 examined October 22. Five hours after milking the count showed 36,750 germs 

 per cubic centimeter. Twelve hours after milking, when kept on ice, the coimt 

 showed 50,180 germs, but at room temperature this had increased to 1,176,000 

 (mean temperature 20 degrees C). The butter fat was 3 per cent. 



Sample No. 31. Producer No. 13. This is from a Ucensed dairy. The 

 sample was received October 22, five hours after milking, at which time there 

 were 261,800 germs per cubic centimeter. Twelve hours after milking there 

 were 316,000 germs per cubic centimeter, in the portion kept on ice, and in the 

 portion kept at room temperature 7,615,000. The butter fat was 2.7 per cent. 



Sample No. 32. Producer No. 14. This is from the same licensed dairy as 

 No. 27. It was examined November 19, five hours after milking, and gave a 

 bacterial count of 4,850. Twelve hours after milking when kept on ice the count 



