ADAMS' METHOD. 119 



ether. If the fat globules have been broken up by a " homo- 

 geniser," the extraction is not complete. 



The following mode of procedure is considered most correct 

 by the author : 



Hang up a convenient number of strips of " fat-free " paper 

 from clamps (letter-clips are very serviceable). Run on, from 

 a pipette, 5 c.c. of each of the samples to be tested in a slow 

 stream, spreading the milk well over the paper ; the strip should 

 be held by its free end, to be nearly horizontal. The weight 

 of the milk delivered by the pipette should be noted, care being 

 taken that it is delivered into the weighing vessel at the same 

 rate and in the same manner as it was run on to the paper. The 

 papers are allowed to hang up till apparently dry ; flies must 

 not be permitted to settle on the surface of the paper, as they 

 consume portions of the fat. 



When the strips are dry enough to handle they should be 

 rolled up in loose coils of a diameter such that they will go easily 

 into the Soxhlet extractors (f to 1 inch), and these should be 

 fastened either by a brass ring, a piece of cotton, or a small pin. 

 A number, or other mark serving to identify the sample, should 

 be placed on each, and a blank coil i.e., one containing no milk 

 should also be rolled up. The coils should be dried at 100 C. 

 for about an hour. 



A sufficient number of wide-necked flasks should be cleaned 

 carefully, and allowed to stand for fifteen minutes inside the 

 balance case. The lightest of these should be placed on the 

 right-hand pan of the balance as a tare, and the others weighed 

 successively against it, the weights required to produce equality 

 being noted. The coils should be placed in the Soxhlet ex- 

 tractors, the flasks fitted, and a measured volume of dry ether, 

 sufficient to fill the extractor well above the upper portion of 

 the siphon, poured into each. The blank coil should be placed 

 in a Soxhlet extractor, and extracted with the same volume of 

 ether into the " tare." The Soxhlet extractors are connected 

 to upright condensers, and the ether boiled by immersing the 

 flasks partially in water at 50 to 60 C. Extraction should 

 be continued for five hours. 



The ether should be distilled off, and the flasks* placed, side 

 downwards, in a drying oven at 100 C. for about twenty minutes, 

 being rotated, and air being blown in every five minutes to remove 

 the vapour of ether. This time is sufficient to dry them if dry 

 ether has been used. 



After cooling for fifteen minutes the flasks should be weighed, 

 the " tare " being again placed on the right-hand pan of the 

 balance, and the percentage of fat calculated from the increase 

 of weight. 



