DETECTION OP ADDED WATER IN MILK. 165 



if a milk is received fresii irom the Inspector a definite pronounce- 

 ment can be made as to whether or not water has been added to the 

 milk. In England, where " the appeal to the cow " is allowed, this 

 is a matter of great importance — in those countries where a definite 

 standard has been adopted it does not matter quite so much. In 

 connection with the milk supply, by far the most important aspect 

 of the question is that from the consumer's standpoint. It matters 

 nothing to the child that is being starved through a supply of poor 

 milk whether the starvation arises from adulteration of the milk with 

 water or through the milkman keeping a bad breed of cows or through 

 his starving a good breed. The offence is equally serious in all cases. 

 Of course, the dairyman with the herd giving a poor yield is not 

 morally on the same plane as the one who deliberately adulterates the 

 milk, but, judging from the consumer's standpoint, he certainly should 

 1)6 prohibited from selling such genuine low-grade milk to the public. 



I might state that in only one case, so far, has an Inspector 

 brought me a sample of milk w^hich was genuine but below our legal 

 standard. The magistrate convicted and fined the defendant, but, 

 of course, the fine was not so hea\y as it would have been had there 

 been deliberate adulteration. 



Given, then, fresh samples of milk, a determination of the acidity 

 and the freezing point will easily distinguish between "natural 

 poverty " and adulteration with water. 



To insure the getting of the samples in a fresh state, the State 

 health inspectors in Queensland pack the samples in ice if they have 

 to travel any distance to this laboratory, and the third, or magis- 

 trate's sample, is immediately on arrival in Brisbane put into the 

 cold storage and kept at about — 2° C. By this means, even when a 

 case is not brought on for a month or two, the magistrate's sample 

 is produced in a fit state for analysis. 



Mr. Brlinnich made a series of experiments on these milks, with a 

 view to using a preservative which, while it would prevent an increase 

 in acidity in the milk for a few days, would not lower the freezing 

 point. All the results obtained are given in Table D, as it is nearlr 

 always advisable to publish full details of work, lack of such details 

 often leading to much work of only negative value being done over 

 and over a^ain by different workers. 



The numbers of the samples refer to the same milks as in Table 

 C, and the various methods of treatment and the results obtained are 

 shown in the table. The first column shows the freezing point of the 

 sample in its original state, the second column shows the rise through 

 the addition of 5 per cent of w^ater. The figures in the third and 

 fourth columns show that "01 per cent, or '015 per cent, of mercuric 

 chloride in alcohol solution does not prevent change while it materi- 

 ally depresses the freezing point, while columns 5 and 6 show the 

 effect on the freezing point of the addition of 5 per cent, and 10 per 

 cent, of water to the milk sample containing '015 per cent, of mer- 

 curic chloride in alcoholic solution. Columns 7 and 8 show that the 

 use of potassium bichromate and formic aldehyde in quantities less 

 than sufficient to preserve the sample materially depresses the freez- 

 ing point. Columns 9 and 10 show that' '01 per cent, or even '02 per 



