Composite Samples of Milk. 161 



it is necessary to adopt the method of collecting drip 

 samples, just explained, or to make use of special sam- 

 pling devices, like the "milk thief," the Scovell, Equity, 

 McKay, and Michels sampling tubes. 1 The 

 principle of these tubes is the same, and it will 

 be sufficient to describe here only a few of them. 

 183. c. The Scovell sampling tube. This 

 convenient device for sampling milk 2 (fig. 52) 

 consists of a drawn copper or brass tube, one- 

 half to one inch in diameter; it is open at both 

 ends, the lower end sliding snugly in a cap pro- 

 vided with three elliptical openings at the side, 

 through which the milk is admitted. The milk 

 to be sampled is poured into a cylindrical pail, 

 or the factory weighing can, and the tube, with 

 the cap set so that the apertures are left open, 

 is lowered into the milk until it touches the 

 bottom of the can. The tube will be filled in- 

 stantly to the level of the milk in the can and 

 is then pushed down against the bottom of the 

 can, thereby closing the apertures of the cap 

 FIG. 52. and confining within the tube a column of milk 



SCOVel 



milk representing exactly the quality of the milk 



sampling 



tube, in the can and forming an aliquot part thereof. 

 The milk in the sampling tube is then emptied into the 

 composite sample jar by turning the tube upside down. 



1 A recent Wisconsin law (Chap. 99, laws of 1907) provides that in 

 sampling cream or milk from which composite tests arc to be made to 

 determine the per cent of butter fat therein, no such sampling shall be 

 lawful, unless a sample be taken from each weighing, and the quantity 

 thus used shall be proportioned to the total weight of cream or milk 

 tested. 



2 Kentucky experiment station, 8th report, pp. xxvi-xxvii. 



11 



