FROM THE PRACTICAL VIEWPOINT 



The same difficulty which is experienced in 

 emptying the tubular heater is observed with rela- 

 tion to the tubular holder. This is due to the very 

 slight inclination or pitch of the tubes from the 

 horizontal. In some cases it has been the prac- 

 tice to force the last milk out of the tubes by fol- 

 lowing it with water. The possibility of adul- 

 terating the milk unless great care is exercised is 

 apparent. In the later machines made, the tubes 

 are given a greater pitch, and the objection due to 

 slow drainage is at least reduced. 



It should be noted that unless the tubes are very 

 thoroughly heated by means of hot water or steam 

 immediately before use, the first milk entering the 

 holder will be so cooled that its temperature at the 

 discharge will be below that which is required. 



This form of holder can be easily cleaned, since 

 the tubes are large, and can be readily opened. 

 It is thus easy to force a suitable brush through 

 the pipes, and it is not difficult to see if all dirt 

 has been removed. It is of course necessary that 

 the cleaning be performed with great thorough- 

 ness in order that it be effective in the destruction 

 of bacteria. 



Whatever form of holder is used, whether it be 

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