114 
EIGHTH REPORT. 
Certain things in this table need explanation. Fifteen samples of Ann 
Arbor water were examined chemically, but thirty-six samples were ex¬ 
amined bacteriologically, and of the thirty-six, fourteen contained 
bacteria that killed animals. Thirteen samples of Battle Creek water 
were examined chemically, while only ten were examined bacteriologic¬ 
ally, and six out of ten contained bacteria that killed animals. 
WATERS FROM SMALL LAKES. 
Table II gives the results of the examination of waters from small 
lakes. 
TABLE II. 
Waters from Small Lakes. 
Place. 
No. 
sample. 
Ammonia. 
Cl. 
No. of 
Germs. 
Effect on 
animals. 
Free. 
Alb. 
Battle Creek. 
10 
.051 
.123 
6.3 
15,183 
5+ 
Cassopolis. 
1 
.070 
.100 
7. 
640 
2+ 
Elk Rapids. 
7 
.204 
1.04 
5.7 
1,185 
5+ 
14 
.150 
.048 
4 3 
5+ 
1 
.018 
.300 
1 
150 
6 
.161 
.294 
4 
23 
Island Lake. 
2 
.202 
.222 
16.5 
549 
1+ 
1 
.154 
.280 
3 
124 
5 
058 
199 
8 
Norway. 
1 
.004 
.010 
9 
20 
1+ 
Negaunee. 
6 
.220 
.454 
20.2 
1,108 
4+ 
2 
.198 
.326 
9 8 
1 
.050 
.250 
4 
50 
1 
1+ 
Average.! 
58 
.124 
.175 
7.3 
1,731 
25+ 
WATERS FROM THE GREAT LAKES. 
I have included among the waters of the Great Lakes those from the 
connecting rivers, such as the St. Clair and Detroit rivers. It will cer¬ 
tainly be understood that most of these cities take thieir supplies not 
directly from the Great Lakes, but from some bay or harbor, which is 
often polluted by the city itself. 
