PHYSICAL AND CHEMICAL EXAMINATION OF MliiK 169 



"The following are the standard Babcock test bottles for milk 

 and cream: 



"1. Milk test bottles, 8 per cent., 18 grams, 6 inch. 



"2. Cream test bottles, 50 per cent., 9 grams, 6 inch. 



"3. Cream test bottles, 50 per cent., 9 grams, 9 inch. 



"Standard milk test bottles, 8 per cent., 18 grams, 6 inch, 1. 

 Graduation: The total per cent, graduation shall be 8. The grad- 

 uated portion of the neck shall have a length of not less than 63.5 

 mm. (2.5 inches). The graduation shall represent whole per cent., 

 five-tenths per cent., and tenths per cent. The tenths per cent, 

 graduations shall be no less than 3 nam. in length; the five-tenths 

 graduations shall be 1 mm. longer than the tenths per cent, grad- 

 uations, projecting 1 mm. to the left; the whole per cent, gradua- 

 tions shall extend halfway around the neck to the right and pro- 

 jecting 2 mm. to the left of the tenths per cent, graduations. Each 

 per cent, graduation shall be numbered, the number being placed 

 on the left of the scale. The error at any point of the scale shall 

 not exceed one-tenth per cent. 



"2. Neck: The neck shall be cylindric for at least 9 mm. 

 below the lowest and above the highest graduation mark. 

 The top of the neck shall be flared to a diameter of not less than 

 10 mm. 



"3. Bulb: The capacity of the bulb up to the junction of the 

 neck shall not be less than 45 c.c. The shape of the bulb may be 

 either cylindric or conical, with the smallest diameter at the 

 bottom. If cylindric, the outside diameter shall be between 34 

 and 36 mm. ; if conical, the outside diameter of the base shall be 

 between 31 and 33 mm., and the maximum diameter between 35 

 and 37 mm. 



"4. The charge of the bottle shall be 18 grams. 



"5. The total height of the bottle shall be between 150 and 

 165 mm. (5| and 6^ inches). 



"6. Each bottle shall bear a permanent identification num- 

 ber. 



"Standard cream test bottles, 50 per cent., 9 gram, so-called 

 6 inch and 9 inch: 1. Graduation: The total per cent, graduation 

 shall be 50. The graduated portion of the neck shall have a 

 length of not less than 63.5 mm. (2^ inches). The graduation 

 shall represent 5 per cent., 1 per cent., and 0.5 per cent. The 0.5 

 per cent, graduations shall be at least 3 mm. in length; the 1 per 

 cent, graduations shall be 2 mm. longer than the 0.5 per cent, 

 graduations, projecting 2 mm. to the left; the 5 per cent, gradu- 

 ations shall extend halfway around the neck to the right and 

 project 4 mm. to the left of the 0.5 per cent, graduations. Each 

 5 per cent, graduation shall be numbered, the number being 



