AGRICULTURAL ENGINEERING. 795 



sion i.s reached that both the keeping quality and character of pear 

 cider is improved bj' filtration after fermentation. 



In another experiment pears, still hard, but which fell easily from 

 the trees, yielded 58 liters of juice per 100 kg-, of fruit. Good, ripe, 

 mellow fruit yielded 65 liters per 100 kg. of fruit; while overripe 

 fruit yielded but 57.2 liters per 100 kg. of fruit. 



The keeping quality but not the taste of pear cider was improved 

 by the addition of sugar and water to the juice before fermentation. 



Wine making- in hot climates, L. Roos, translated by R. Dubois and W. P. 

 Wilkinson (Mclhoimie: florcrnmeiii, 1900, i^p. i^73, pl'^. 4, . figs. .59). — This is one of the 

 pul )lications of the Viticultural Station of the Department of Agriculture of Victoria, 

 Australia, located at Rutlierglen. 



The use of yeast in making- currant wine, W. Keliiofer {Jaliresber. Vers. Stat. 

 u. Schide, Wademiveil, 1897-98, pp. 53-57). — Pure yeast cultures, beer yeast, dry 

 pressed yeast, and no artificial addition of yeast whatever, were used in making 

 currant wine. The chemical composition of the wine produced in each case is tabu- 

 lated. The conclusion is reached that when pure yeast for wine-making can not be 

 olitained, a good wine for household purposes can he made by the use of fresh beer 

 yeast at the rate of 50 cc. per hectoliter of juice. Next in value would be newly- 

 made dry yeast, using 20 gm. for each hectoliter of juice. The fermentation of 

 berries and juice together resulted in bad-tasting wine which easily spoiled. 



Wine making- in Russia, M. Ballos {St. Petersburg: Department of Agriculture, 

 1899, pt. 5, pp. XV— 455; rev. in Selsk. Khoz. i Lyesov., 196 {1900), Feb., p. 469).— This 

 volume is devoted to a descrijition of the industry in Southern Russia. 



The briar root industry in Italy (>S'c(. Amer. Sup., 50 (1900), Xo. 1292, p. 

 20718). — A record of the production of the root of Erica arborea for use in making 

 tobacco pipes. 



AGRICULTURAL ENGINEERING. 



Water resources of Porto Rico, H. M. Wilson ( Water Supp^i/ 



and Irrhjaflon Papers^ U. S. GtoJ. Survey, JSfo. 32^ pj). Jt-8^ j9/.s-. X5, 

 rnajys 2, figs. 10). — This is a report based on notes, sketches, and pho- 

 tographs collected b}^ the author "during a brief journe}" made 

 through the Island of Porto Rico in January, 1899. The object of 

 this trip was primarily to study the topographic characteristics and 

 the water resources of the island, but incidentally numerous memo- 

 randa relative to the soil, agricultural products, and forests were 

 obtained." 



The following topics are discussed: Topographic relief — coastal to- 

 pography, and physiography and scener}^; climatolog;\' — precipitation 

 and temperature; hydrograph}' — irrigation; agricultural lands and 

 soil — old fields and fertilizers, and agricultural products; forestry; 

 water power and supply; and transportation facilities. 



On about three-fourths of the area of the island (north side) the 

 rainfall is sufficient for crops. 



"The other one-fourth, including all the region near the coast and from Cabo 

 Rojo on the extreme west to beyond Guayama on the east, must be irrigated if the 

 soil is to produce the full measure of crops of which it is capable. The total area of 

 these iiTigable lands is, however, relatively small. . . . 



