68 



ELEMENTS OF WATER BACTERIOLOGY 



RELATION OF 20° AND 37° COUNTS IN SAMPLES OF 

 WATER FROM APPARENTLY UNPOLLUTED SOURCES 



(WiNSLOW AND NiBECKER, I903) 



Source of Samples. 



Cambridge supply (tap) 



Wakefield and Stoneham supply 



(tap) 



Lynn supply (tap) 



Brookline supply (tap) 



Plymouth supply (tap) 



Peabody supply (tap) 



Dedham supply (tap) 



Newburyport supply (tap) 



Salem supply (tap) 



Taunton supply (tap) 



Sharon (well) (tap) 



Medford supply (tap) 



Milton supply (tap) 



Westerly, R. I., supply (tap) 



Brooks ■. 



Driven wells 



Springs 



Ponds fed by brooks 



Melted snow 



Pools in fields 



Pools in woods 



Roadside pools 



Stream, Blue Hill Reservation. . . . 



Flow from rocks 



Ponds fed by springs 



Drainage from manured pasture . . 



Swamps 



Rain-water after twelve hours' 



heavy fall 



Shallow well in Lynn woods 



Totals 



c o 



3 C 



94 



59 

 16 



35 

 141 



3717 



36 



232 



13 



738 



524 



4700 



223 



18 



294 



iSI 167 



365 

 181 

 811 



47 

 188 



1235 

 269 



15 



Litmus- 

 lactose- 



agar 

 Plates, 



37°. 



0) 



60' S 

 S o 



Dextrose-Broth 

 Tubes. 



15 



21 

 18 



3 



18 



Q 

 18 

 18 



IS 

 12 



9 



15 

 6 



3 



183 



45 



95 



45 



3 

 66 



65 

 30 

 3 

 6 

 18 

 3 

 9 



21 

 3 



"SO 





H« 



6-S 



259 



775 



41 



38 



