THE CHEMISTRY OF COOKERY. 777 



flow down a single channel, it would form a respectable little rivulet. 

 An interesting example of the self-adjusting operation of demand and 

 supply is presented by the fact that, without any special legislation or 

 any dictating official, the quantity required should thus flow with so 

 little excess that, in spite of its perishable qualities, little or none is 

 spoiled by souring, and yet at any moment anybody may buy a penny- 

 worth within two or three hundred yards of any part of the great 

 metropolis. There is no record of any single day on which the supply 

 has failed, or even been sensibly deficient. 



This is effected by drawing the supplies from a great number of 

 independent sources, which are not likely to be simultaneously dis- 

 turbed in the same direction. Coupled with this advantage is a serious 

 danger. It has been unmistakably demonstrated that certain microbia 

 (minute living abominations) which disseminate malignant diseases 

 may live in milk, feed upon it, increase and multiply therein, and by 

 it be transmitted to human beings with very serious and even fatal 

 results. 



I speak the more feelingly on this subject, having very recently had 

 painful experience of it. One of my sons went for a holiday to a 

 farm-house in Shropshire, where many happy and health-giving holi- 

 days have been spent by all the members of my family. At the end 

 of two or three weeks he was attacked by scarlet fever, and suffered 

 severely. He afterward learned that the cow-boy had been ill, and 

 further inquiry proved that his illness was scarlet fever, though not 

 acknowledged to be such ; that he had milked before the scaling of 

 the skin that follows the eruption could have been completed, and it 

 was therefore, most probable, that some of the scales from his hands 

 fell into the milk. My son drank freely of uncooked milk, the other 

 inmates of the farm drinking home-brewed beer, and only taking milk 

 in tea or coffee hot enough to destroy the vitality of fever-germs. He 

 alone suffered. This infection was the more remarkable, inasmuch as 

 a few months previously he had been assisting a medical man in a 

 crowded part of London where scarlet fever was prevalent, and had 

 come in frequent contact with patients in different stages of the 

 disease. 



Had the milk from this farm been sent to London in the usual 

 manner in cans, and the contents of these particular cans mixed with 

 those of the rest received by the vender, the whole of his stock would 

 have been infected. As some thousands of farms contribute to the 

 supplying of London with milk, the risk of such contact with infected 

 hands occurring occasionally in one or another of them is very great, 

 and fully justifies me in urgently recommending the manager of every 

 household to strictly enforce the boiling of every drop of milk that 

 enters the house. At the temperature of 212 the vitality of all dan- 

 gerous germs is destroyed, and the boiling-point of milk is a little 

 above 212. The temperature of tea or coffee, as ordinarily used, 



