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destruction of organic life already in existence in the milk, so that if it is kept 
from the air, and no foreign substance is allowed to enter, it is perfectly pure: 
and wholesome for human consumption. 
In the Laval Pasteuriser, consisting of a double-jacketed vat, in the centre- 
of which is an agitator kept in motion by a steam turbine under the bottom of 
the vat, the milk is exposed to the heat during the shortest possible time, and, 
leaving the apparatus at 160 degrees Fahr., is instantaneously cooled down on 
the cooling apparatus to nearly the same temperature as in the cooling water 
applied for the purpose. This apparatus, being most ingeniously designed, 
combines the greatest cooling surface in the smallest space, and as the fluid to. 
_ be cooled flows over its outer and inner surfaces the cooling water takes up the 
heat, and expels at the same time the scalded taste and other gases, leaving the 
milk or cream sweet and fresh and beautiful to the palate. Thus, it will be- 
understood, the pasteurisation consists of an instantaneous heating to 160 
degrees Fahr., which is followed by the cooling of the milk or cream to, say,. 
50 degrees Fahr., the cooling being just us necessary as the heating. The: 
latter destroys microbes, bacteria, tubercula, bacilli, &e , and the cooling checks. 
the lower grade of spores and stops their development, removes the heated 
flavour, and restores the chemical composition of the milk to its original, 
consistency. This treatment of the milk for town use is now being generally 
introduced in the cities of Europe, and also already adopted by a well-known 
milk-supplier in Brisbane, which is without doubt most beneficial to the health. 
of the public, and especially that of the children. 
Pasteurising of milk for human consumption will, we do not hesitate to say, 
before long be compulsory by law. 
IFES 
