274 MILK AND ITS HYGIENIC RELATIONS 



unsterilised article after having washed their hands prior to 

 milking. The hands should be washed between the milking 

 of each cow. On some farms the overalls and caps worn are 

 sterilised in steam; in others they are merJy kept clean by 

 frequent washing. 



Milking machines have been invented with a view to the 

 economy of labour and also from a desire to obviate some of the 

 possible contamination of milk from an unclean or diseased 

 milker. At first these milking machines were not found very 

 satisfactory, because they did not milk the cow completely, 

 but left behind much of the strippings, which have been shown 

 on p. 22 to contain the highest fat content. As a result of this 

 unsatisfactory emptying of the gland, the cows tended to go ' dry/ 

 More recently, milking machines have been invented which are 

 stated to milk the cows more completely, although it seems that 

 certain cows can never be milked completely with the machine 

 but must be stripped by hand afterwards. So long as stripping 

 is accomplished the use of the milking machine does not appear 

 to have any injurious effects upon the cows, nor to reduce the 

 yield of milk.* 



The milking machines are said to economise labour, as several 

 cows can be milked at the same time, but the discussions of dairymen 

 reported from America hardly suggests complete uniformity of 

 opinion. Regarded from the hygienic aspect in relation to the milk 

 supply, it seems difficult to believe that the milking machine is not a 

 step backwards. The rubber tubes are known to be very difficult to 

 cleanse, and flexible tubes must be used in view of the probable 

 movement of the cows. Unless these machines are used with a 

 care and cleanliness which can hardly be expected of anyone with- 

 out a bacteriological training, it is greatly to be feared that they 

 will prove an insidious variety of the old long-tubed feeding-bottles, 

 now justly condemned as a death-trap for infants. A milking 

 machine is shown in the accompanying plate. The tubes are 

 applied to the several teats, and a reduction of pressure in 

 the can is produced. By this means the milk is sucked into 

 the can. 



The pail used is a matter of very considerable importance. 

 The old-fashioned open pail should not be used. A hooded pail, 

 or one with a side aperture, gives greatly superior results, and the 

 pail which has a side aperture only, is said to be superior to the 

 hooded variety. These pails, which are shown in the figure, p. 275, 

 prevent the contamination of the milk, by bacteria from the cow or 

 from the air, which may, and usually do, fall into the milk-pail 

 from above. 



The following figures, which were obtained as a result of bacterio- 

 logical experiments recently made at Birmingham at four good 



* Cp. Mairs. 



