11 



Page 51, under " Optional method of standardizing flasks, " insert 

 the following in place of the method there given: 



The following formula may be used for calculating the weight of water (W T ) which a 

 given flask will hold at T (weighed in air with brass weights at the temperature of the 

 room) from the weight of water (W to ) (weighed in air with brass weights at the temperature 

 of the room) contained therein at t: 



W To =W to_d^ (1+r (T-t)) 



d T = the density of water at T. 

 d 4 = the density of water at t. 

 ^=the coefficient of cubical expansion of glass. 



(See also " Separation of Milk and Cheese Proteids," page 20 of this 

 circular.) 



Page 52, under "(1) Determination of melting point Wiley's 

 method, (3) Determination," end of the first paragraph, insert as fol- 

 lows: "These disks should be prepared a day, or at least a few hours ; 

 before using." 



Page 55, change paragraph 3 to read as follows: 



3. Official optional method for determining casein. To 10 cc of milk add 50 cc of distilled 

 water at 40, then add 2 cc of alum solution saturated at 40 or higher. Allow precipitate 

 to settle, transfer to a filter, and wash. The washed precipitate and filter paper are digested 

 as in regular Kjeldahl method, as outlined in the official method, paragraph 1. Calculate 

 casein by multiplying the amount of nitrogen found by 6.25. 



Twenty-second Convention, 1905, Bui. 99, Cir. 26. 



Page 49, change correction for temperature for index of refraction 

 from 0.000176 to 0.000365. [Resultant corrections should be made.] 



ERRATA. 



Compare the following: Page 43, section (c) (2), second line, "or 

 with 76 petroleum ether ", with page 54, section 2. (b) (1), next to the 

 last line, "ether or petroleum ether boiling at about 45 ". 



V. METHODS FOR THE ANALYSIS OF FERMENTED AND DIS- 

 TILLED LIQUORS. 



No changes have been made in this section except in so far as it has 

 been modified in practice by the provisional methods introduced in the 

 food adulteration work, which methods are given in Bulletin 65, and 

 in Circular 29, giving changes in and additions thereto. 



ERRATUM. 



Page 64, section (8) (a) fourth line, for " 11" read " 12 ". 



