640 



SCIENCE 



[N. S. Vol. XXXVIII. No. 983 



probably present, for the most part, in the free 

 state. Currants always contain citric acid, and 

 may or may not contain malic acid. Gooseberries 

 contain large amounts of both malic and citric 

 acids. In persimmons and bananas, malic acid 

 probably occurs alone. The pomegranate and canta- 

 loupe contain citric acid, probably without malic 

 acid. In the watermelon, quince and peach, malic 

 acid predominates, and citric acid is probably ab- 

 sent. Cranberries contain both malic and citric 

 acid. Red raspberries contain citric acid, with 

 malic acid present in traces, if at all. Blackber- 

 ries contain citric acid in some cases, while some 

 samples contain traces of malic acid without citric 

 and in others neither malic or citric acids could be 

 identified. The acid of the apricot has not been 

 positively identified. There is present some dextro- 

 rotatory acid whose rotation is increased by the addi- 

 tion of uranyl acetate — possibly tartaric or dextro- 

 malic acid. The acid of the huckleberry has not 

 been positively identified. Traces of malic acid 

 without citric appear to be present. Tartaric acid 

 was not found in any of the fruits examined, 

 with the possible exception of apricots. In the 

 case of pears, Kiefifer, Le Conte, Idaho and Bart- 

 lett contain little or no malic, while citric acid ap- 

 pears to predominate. In all other varieties the 

 acidity appears to be due mostly or entirely to 

 malic acid. 



The paper also includes a review of the litera- 

 ture on the acidity of fruits, with the results ofl 

 various writers presented in tabular form. 



J. A. BizzELL and T. L. Lyon: Estimation of the 



Lime Bequirement of Soils. 



The authors propose a modification of the 

 method described by R. Albert^ for estimating the 

 lime requirement of soils. The modified method 

 is as follows : 



Place 25 grams of the air-dried soil in a Jena 

 kjeldahl flask. Cover with 50 c.c. boiled distilled 

 water and add 50 c.c. tenth normal barium hydrox- 

 ide solution. Digest in a briskly boiling water 

 bath for one hour with occasional shaking. Re- 

 move from the water bath, add 150 c.c. distilled 

 water andi5 grams solid ammonium chloride. Con- 

 nect the flask with a nitrogen distillation apparatus 

 and distill. Collect the distillate (150 c.c.) in 

 tenth normal acid, and titrate, using methyl-orange 

 as indicator. The strength of the barium hydrox- 

 ide is determined by titrating directly 50 c.c. of 

 the solution, using methyl-orange as indicator. 

 The difference between the two titrations, there- 



1 Zeit. f. Angewandte Chem., I., p. 533. 



fore, represents the amount of barium hydroxide 

 absorbed by the soil. A correction is made for the 

 slight decomposition of ammonium chloride when 

 heated with soil. 



The results obtained on 22 samples of soil accord 

 fairly well with those obtained by the Veitch lime- 

 water method. 



H. V. Tartar: The Valuation of the Lime-sulphur 



Spray as an Insecticide. 

 L. M. ToLMAN and J. G. Rilet: The Effects of 



Maw Materials on the Chemical Composition of 



American Beer. 

 Floyd W. Robinson: Food Standards and their 



Effect upon Food Law Enforcement. 

 J. F. Snell and J. M. Scott: The Analysis of 



Maple Products. II.: A Comparative Study of 



the Delicacy of Methods. 



The authors compare the range of variation of 

 conductivity value, ash data and Winton, Ross and 

 Canadian lead values in genuine maple syrup and 

 the rates at which these data diminish as sucrose 

 syrup is admixed. 



Conductivity value shows narrowest range, Ca- 

 nadian lead value most rapid diminution. Winton 

 value has much narrower range than Canadian and 

 gives closer duplicates. In Canadian method 

 wash water may be indifferently 80° or 100° C. 

 and 100 or 150 c.c. Lead values on basis of fixed 

 quantity dry matter by (1) calculation, (2) di- 

 rect determination do not accord. 



DIVISION of organic CHEMISTRY 



Treat B. Johnson, Chairman 

 William J. Hale, Vice-chairman and Secretary 

 E. Kohmann and Treat B. Johnson: The Struc- 

 ture of Urushiol, a Component of Japanese Lac. 

 S. F. ACREE: The Reactions of Both the Ions and 

 the Non-ionized Forms of Adds, Bases and 

 Salts. 

 Wm. Lloyd Evans and Charles E. Parkinson: 

 The Existence of Mandelic Aldehyde in Aqueous 

 Solution. 



Mandelic aldehyde acetal was prepared by the 

 reduction of benzoylformaldehyde acetal, which in 

 turn was made by the interaction of dibromaceta- 

 phenone and sodium ethylate. Mandelic aldehyde 

 acetal hydrolyzes in the presence of sulfuric acid, 

 both at ordinary temperature and at 0°, the inter- 

 mediate compound formed undergoing a rear- 

 rangement to benzoyl carbinol. This hydrolysis 

 takes place also by means of the water vapor of 

 the atmosphere. The same rearrangement was ob- 



