456 TRANSACTIONS OF SECTION B. 
had frequently been examined by their bacteriologist and chemist; they 
consequently felt convinced that no antiseptic could have been added. The 
dairymen indignantly denied having tampered with the milk, and claimed 
to have used every known precaution to make their certified milk the best 
in the market. We found, after long investigation, variable minute quan- 
tities of copper in the bottles of certified milk examined. In tracing the 
origin of the copper salts it developed that the boiler compound (used on 
account of the hard water) primed or foamed over, thereby contaminating 
the sterilising cloths, pails, and other utensils which came in contact with 
the milk. In order to find out if such minute quantities of copper could 
alter the milk, check experiments with and without the addition of copper 
salts were made; also differences in the behaviour of the same milk caught 
direct in broad-mouthed bottles and that obtained at the dairy in the usual 
mode of procedure were observed. Experiments showed that copper salts are 
selective in their actions, either greatly retarding or inhibiting the putre- 
factive bacteria, such as Proteus vulgaris, mirabilis, Zenkeri and Clos- 
tridium fatidum, but, on the other hand, having but little effect upon the 
Lactic bacteria; consequently milk treated with these salts retained its 
sweet odour even if the acidity contents became sufficiently high to curd it. 
Moulds such as Penicillium glaucum, Aspergillus niger, Eurotium repens, 
and others, probably because left; a freer field for development, grow much 
more profusely upon the certified milk than on other milks not treated with 
copper salts. Tests with copper salts clearly demonstrated their anti- 
putrescent effect in blood albumin, egg albumin, meat, milk, and sewage 
solutions. Even after nine months’ submersion in dilute copper solutions 
there was no great change in the taste and odour of eggs, and, though left 
in the same position, the yolks did not adhere to the shells. 
6. Report on the Study of Isomorphous Sulphonic Derivatives of 
Benzene.—See Reports, p. 141. 
7. Report on Electroanalysis.—See Reports, p. 144. 
8. Report on the Study of Hydro-aromatic Substances. 
See Reports, p. 145. 
9. Report on the Transformation of Aromatic Nitroamines and Allied 
Substances, and its Relation to Substitution in Benzene Deriva- 
tives.—See Reports, p. 147. 
FRIDAY, AUGUST 27, 
Joint Meeting with Section A.} 
The following Report and Papers were read :— 
1, Report on Dynamic Isomerism.—See Reports, p. 135. 
2. On the Constancy of the Hydrogen Gas Electrode. 
By Cuartss J. J. Fox, B.Sc., Ph.D. 
The author has investigated the constancy of the hydrogen gas electrode 
in H.SO, and HCl, when gold, platinum, and palladium coated with 
* See also Section A, p, 394, 
