1917] METEOROLOGY. 15 



or racemizatlon, and that the rotatory power of an aqueous solution of nlcotin 

 containing 3 per cent of the base or less Is proportional to its concentration, is 

 proposed. 



The procedure described consists of distilling the nlcotin with barium hy- 

 droxid by a current of steam, acidifying the distillate with sulphuric acid, 

 and then evaporating to about 50 cc. volume. The concentrated solution Is 

 made to volume and then made strongly alkaiine with concentrated KOH fol- 

 lowed by a few drops of barium hydroxid. This last addition is not essential, 

 but tends to clarify the solution when any turbidity is developed. The liquid 

 is again made to volume, the precipitate allowed to settle, and, after filtering 

 the supernatant liquid, the filtrate is examined in a polarimeter. The calcula- 

 tions for the amount of nlcotin present from the polarimetric readings are 

 described. 



A slightly modified procedure in which the distillate is not acidified, bul 

 extracted with chloroform and the chloroform extracts treated with sulphuric 

 acid In a separatory funnel is also described. After heating to expel the dis- 

 solved chloroform the solution is made alkaline with KOH and the filtrate 

 then examined polarimetrically. 



The method yields higher results and is considered to be more accurate than 

 the Kissling procedure, which is official. 



Sirups for canning and preserving, J. B. McNatb {Jour. Indus, and Engin. 

 Chem., 9 {1917), No. 2, pp. 151-153. fig. i).— Tables showing number of the 

 gallons of water or ounces of sugar per gallon of sirup required to change 

 a sirup from a given degree Brix to another given degree Brix at 17° C, 

 changes in volume (in parts per 10,000) of sirups at different temperatures, 

 and the correction for the readings of Balling's saccharimeter on account of 

 temperature are submitted and their use described. 



The value of such data in connection with the preparation of fruit jellies 

 is indicated. 



The manufacture of apple jelly, A. Truelle {Vie Agr. et Rurale, 6 {1916), 

 No. Jf6, pp. 357-361. figs. 2). — This is a general discussion of English methods 

 of preparation, together with the results of some original experiments by the 

 author. 



A table giving the grams of acid (as malic), tannin, and pectin in 100 cc. 

 of the juice of 50 varieties of apples is included. 



METEOKOIOGY. 



The quantitative study of cUmatic factors in relation to plant life, J. 

 Adams {Proc. and Trans. Roy. Soc. Canada, 3. ser., 10 {1916), Sect. IV, pp. 

 105-123). — This article discusses the relations of temperature, light, precipita- 

 tion, evaporation, and wind to plant growth at various places in Canada and 

 makes certain general deductions as to such relationships. 



World-wide changes of temperature, C. F. Brooks {Sci. Amer. Sup., 8S 

 {1917), No. 2152. pp. 194, 195; Geogr. Rev., 2 {1916), No. 4, pp. 249-255).— This 

 article deals primarily with the possibility of seasonal forecasts. It is stated 

 that " the weather in widely separated parts of the earth is correlated because 

 of the extensive control of the large belts and centers of atmospheric 

 action. . . . These are subsequent, however, to changes in the sun's radiation, 

 which produce immediate, world-wide pressure alterations. Any possibilities 

 for widespread seasonal forecasts must rest, therefore, first on an ability to 

 forecast solar changes and, second, on a knowledge of the immediate and sub- 

 sequent atmospheric effects of such variations." 



