METEOROLOGY WATER. 117 



The changes taking place in the leaf top in air curing consist of an entire 

 loss in starch and reducing sugars, a decrease of pentosans and malic acid, and 

 an increase in citric acid, while the cellulose content remains unchanged. 

 " There is a large decrease in protein, in some cases amounting to 60 per cent 

 of the total, and a considerable decrease in nicotin and total nitrogen. Appre- 

 ciable quantities of ammonia are formed in the process. In the curing of 

 picked leaves the chemical changes appear to be due almost wholly to re.spix'a- 

 tion, while in curing the leaves on the stalk the phenomenon of translocation 

 from the leaf into the stalk plays an important role. This translocation, 

 which constitutes the essential physiological difference in the two methods of 

 curing involves the transfer into the stalk of the amid and amido compounds 

 derived from the protein, ammonia, and a portion of the mineral constituents, 

 nitrate, and, doubtless, a portion of the carbohydi'ates. The picked leaves after 

 curing contain, therefore, much larger quantities of amid and amido com- 

 pounds, and ammonia, and somewhat larger quantities of mineral matter and 

 nitrate than the leaves cured on the stalk. 



"The physiological processes characteristic of tobacco curing indicate the 

 presence of diastatie, proteolytic, and deamidizing enzyms, and probably also of 

 oxidases. The process of starvation to which the leaves are subjected leads to 

 an increased secretion of diastase during the progress of the curing. Tempera- 

 ture has a very marked effect on the rate of curing. The rate of curing in- 

 creases very rapidly with rise in temperature up to the killing point of the 

 protoplasm (about 130° F.). The moderate use of artificial heat in air curing 

 does not materially affect the final result in curing so far as measured by the 

 ordinary methods of chemical analysis, provided other conditions remain favor- 

 able in both cases. Thorough wilting in the initial stages of the curing pro- 

 moter the progress of the process, provided the further drying of the leaf is not 

 allowed to proceed too rapidly." 



The experimental error in sampling sugar cane, J. W. Leather (Mem. 

 Dcpt. Ayr. India, Chcm. So:, 3 (1913), No. 4, pp. 107-133, fig. i).— The results 

 tabulated are those obtained in the experimental grounds at Pusa and a sugar 

 factory at Parsa, India. 



The clarification of Louisiana cane juices, W. E. Cross (Louisiana Stas. 

 Bui. 144 (1914), PP- 39). — The studies recorded in this bulletin deal with the 

 sulphitation and the carbonation processes for the clarification of cane and beet 

 juices. They were carried on in the laboratory and sugarhouse of the Sugar 

 Experiment Station, and preliminary reports on certain parts of the work have 

 already appeared in the scientific literature. A chapter on treating sirup is 

 also included. 



METEOKOLOGY— WATER. 



Meteorological observations, J. S. Stevens (Maine Sta. Bui. 222 (1913), pp. 

 319, 320). — Observations at Orouo. Me., on temperature, precipitation, cloudi- 

 ness, and wind during 1913 are compared with the means of similar observa- 

 tions for 45 years. The mean temperature for 1913 was 45.45° F., the mean for 

 45 years 42.57° ; the precipitation for 1913 was 44 in., for 45 years 43.33 in. ; 

 the snowfall for 1913 was 34.3 in., for 45 years 90.4 in. ; the number of days on 

 which there was a precipitation of 0.01 in. or more was 112, the number of clear 

 days 126, and the number of cloudy days 140 ; and the total movement of wind 

 in miles, 52,484. 



Surface water supply of the Missouri River Basin, 1911, W. A. Lamb, 

 W. B. Freeman, and R. Richards (U. 8. Geo!. Survey, Water-Supplij Paper 

 306 (,1914), PP' ^'^4' P^s. 4). — This paper presents results of measurements of 



