170 



TEE AGRIGULT 



URAL JOURNAL. 



bottles should always be labelled 

 "Poison," and kept out of the reach of 

 children when not in use. 



Measuring the Acid. 

 The acid is measured with a 17.5 c.c. 

 glass measure, and poured down the in- 

 side of the neck of the test flask with- 

 out disturbing the milk. The test flask 

 should be held at an angle to allow the 

 air to come out as the acid goes in, to 

 prevent spilling. The test samples may 

 be shaken separately by hand or together 

 m a cradle. It is possible to dissolve 

 the milk in less than the quantity of acid 

 added, and sometimes a clear layer of 

 acid remains at the bottom. This can 

 be overcome by giving the bottles a good 

 shaking with a reverse motion before 

 linishing. 



Whirling the Bottles. 



The speed at which the machine has 

 to be turned depends on the gearing, and 

 the diameter of the testers. If the 

 bottle-wheel of the machine is 12 inches 

 in diameter, that wheel should be made 

 to turn 980 times per minute. If 18 

 inches in diameter, 800 revolutions per 

 nnnute, and if 24 inches in diameter, 

 693 revolutions per minute. If the bot- 

 tle-wheel is. 18 inches in diameter, and 

 geared to revolve ten times for one turn 

 of the handle, the operator should turn 

 the handle 80 times per minute to attain 

 the necessary speed. If the bottle-wheel 

 be geared by friction, care should be 

 taken that no slipping takes place. For 

 factory or creamery use the steam-tur- 

 bine machines are far preferable to the 

 others. 



Adding the Water. 

 After turning the tester for six 

 minutes, hot water, 180 deg., is added 

 uj) to the neck of the flasks. Rain or 

 soft water should be used for this pur- 

 pose. After adding the water the 

 machine is turned for three minutes, then 

 more water is added to bring the liquid 

 lip in tlie neck of the flask to between the 

 7 and 10 mark. Another minute's turn- 

 ing, and the operation is complete. If 

 only a few samples are to be rested, the 

 water may be added with the milk 



pipette ; but where a large number have 

 to be done a can with a rubber tube and 

 pinch-cock is handiest. 



Reading the Tests. 



A pair of fine-pointed dividers is of 

 great assisUiuce m taking the measure- 

 ment of the tat column. The fat is 

 measured from the lower line between it 

 and the water to the top of the column. 

 Having taken that span with the divi- 

 ders, one point is placed at 0, and the 

 other will show the percentage of fat on 

 the scale on the neck of the bottle. 

 Each large division represents 1 per 

 cent., and each small space two-ten ; is 

 or 0.2 of 1 per cent. In very cold 

 weather the fat column often partly 

 solidifies before a reading can take place. 

 This may be prevented by keeping up 

 the temperature of the samples. Hot 

 water may be put in the pan of the 

 machine, and the test flasks placed in 

 warm water after whirling is finished, 

 until the readings are recorded. This 

 precaution is not necessary tor tlie 

 greater part of the year. 



Computing the Butter Contents. 



In order to arrive at the eommercial 

 butter contents in milk per the respec- 

 tive butter-fat percentage, it is necessary 

 to deduct a small loss that takes place in 

 skimming, plus another loss that occurs 

 in churning, and then add a percentage 

 to make up for the usual quantity of 

 water, curd, and salt contained in com- 

 mercial butter. As a net addition is dif- 

 ferent with each test it is impracticable, 

 as well as a waste of time, to work out 

 each result in such a roundabout method. 

 The following table of test values agrees 

 Avith the Babcock table adopted by most 

 of our factories. All milk should be re- 

 duced to butter, per its test, before quot- 

 ing its money value. This system is 

 more precise and equitable than differ- 

 ential rates per gallon, and is not liable 

 to many misleading and complicated in- 

 terpretations. Many useful hints, to- 

 gether with detailed instructions, are gen- 

 erally issued hy the makers of each 

 machine. Beginners should take a few 

 lessons in the use of the Babcock tester 

 from someone who has had experience. 



