The human hand, even if washed frequently, is a difficult thing to keep scientifically clean. The milkman has to put his hand now on the cow's side, now on his stool; in short, he is constantly touching surfaces which cannot be guaranteed germless. He may, therefore, infect the teats, which in turn infect the milk. So that, for health's sake as well as to minimise the labour and expense of milking, various devices have been tried for mechanically extracting the fluid from the udder. Many of these have died quick deaths, on account of their practical imperfections. But one, at least, may be pronounced a success--the Lawrence-Kennedy cow-milker, which is worked by electricity, and supplies another proof of the adaptability of the "mysterious fluid" to the service of man.
On the Isle de la Loge in the Seine is a dairy farm which is most up-to-date in its employment of labour-saving appliances, including that just mentioned. Here a turbine generates power to work vacuum pumps of large capacity. The pumps are connected to tubes terminating in cone-shaped rubber caps that can be easily slipped on to the teat; four caps branching out from a single suction chamber. As soon as they have been adjusted, the milkman--now shorn of a great part of his rights to that title--turns on the vacuum cock, and the pulsator, a device to imitate the periodic action of hand milking, commences to work. The number of pulsations per minute can be regulated to a nicety by adjusting screws. On its way to the pail the milk passes through a glass tube, so that the operator may see when the milking is completed.
This method eliminates the danger of hand contamination. It also protects the milk entirely from the air, and it has been stated that, when thus extracted, milk keeps sweet for a much longer time than under the old system. The cows apparently do not object to machinery replacing man, not even the Jersey breed, which are the most fidgety of all the tribe. Under the heading of economy the user scores heavily, for a single attendant can adjust and watch a number of mechanical milkers, whereas "one man, one cow" must be the rule where the hand is used. From the point of romance, the world may lose; the vacuum pump cannot vie with the pretty milkmaid of the songs. Practical people will, however, rest content with pure milk _minus_ the beauty, in preference to milk _plus_ the microbe and the milkmaid, who--especially when she is a man--is not always so very beautiful after all.