334 
METHODS OF ANALYSIS. 
SAMPLING. 
It has been found extremely difficult to take samples of 
butter from the same package and obtain concordant results 
by analysis. This is principally due to the fact that the 
water is not uniformly distributed throughout the mass, 
and mixing or working tends rather to separate the water 
than to distribute it. tee 
As this waiter is usually a saturated solution of salt, the 
sampling effects directly the water and the ash, and indi- 
rectly all of the other constituents. ~ | 
Atter trying various methods of sampling without suc- 
cess, the following was adopted and found to be very satis- 
factory, in so far that duplicate analyses of the same sample 
gave results which agreed closely. 
A quantity of butter, large enough to represent the von- 
tents of the package from which it is taken, is placed in a 
wide mouthed, glass stoppered bottle or fruit jar, and 
melted by immersing the bottle in warm water. - When 
the whole sample is melted the bottle is shaken vigorceusly 
and the shaking continued till the butter is again in a solid 
condition. The cooling may be hastened by immersing the 
bottle frequently in cold water. In this way a homogen- 
eous mixture of all the constituents is obtained and the 
water is so. finely divided that separation will not take place, 
so long as the butter is kept cool. 
WATER. 
The estimation of water is effected with the same appara- 
tus and in the same manner as the solids of milk. (See 
Second Annual Report of this Station, page 168). The 
apparatus consists of a perforated test-tube about 5 inches 
long in the bottom of which is placed a tuft of clean cotton, 
and upon this sufficient ignited asbestos to fill the tube three- 
fourths full. The asbestos should be slightly pressed 
together to avoid large spaces, and a plug of cotton placed 
ny the mouth of the tube to prevent the escape of loose 
ers. 
After weighing the tube the plug of cotton is removed, 
about 3 grams of butter put in and the cotton replaced. The 
tube is then placed in a drying oven, in an upright position, 
till the butter is melted and absorbed by the asbestos. A 
current of dry air is afterwards forced through the tube, 
which is kept at 100° C. till the weight is constant. 
FAT. 
The tube containing the dry butter from the water deter- 
mination is transferred to an extraction apparatus and ex- 

2 
12% se 
aaa 

