TABLE XXI.—AFTERGROWTHS IN SAND
| Available in Water p.p.m. | Bacteria Per Gram of Sand After | ||
| 3 Hours. | 24 Hours. | 48 Hours. | |
| Nil | 70,000 | ..... | ..... |
| 0.1 | 7,200 | 20,400 | 12,800 |
| 0.3 | 5,240 | 6,400 | 11,200 |
| 0.5 | 5,120 | 4,700 | 10,800 |
| 1.0 | 1,100 | 8,800 | 20,400 |
It is observable that the effect of small doses was comparatively small and transient; large doses of bleach reduced the bacteria very materially but the reduction was not maintained and the subsequent increase was abnormally rapid.
BIBLIOGRAPHY
[1] Wesbrook, Whittaker and Mohler. J. Amer. Pub. Health Assoc., 1911, 1, 123.
[2] Thomas. Jour. Ind. and Eng. Chem., 1914, 6, 548.
[3] Smeeton. Jour. of Bact., 1917, 2, 358.
[4] Clark and De Gage. Rpt. Mass. B. of H., 1910, p. 319.
[5] Thomas and Sandman. J. Ind. and Eng. Chem., 1914, 6, 638.
[6] Jordan, H. E. Eng. Record, 1915, May 17.