722 TRANSACTioys OF THE Amehican Institute. 



it is poured into a clean vessel and cooled down to lOi degrees or 100 

 degrees Fahr. In the meantime a quantity of water is brought to 

 the boiling point, and in forty-five parts of it by weight, fifteen parts 

 of bichromate of potash are dissolved. When the solution has cooled 

 a little, sixty parts of hydrochloric acid are added and then the palm 

 oil is poured in, the whole being well stirred during the process of 

 mixing, and still continued until the oxyd of chromium becomes 

 completely separated. The oil assumes, within a few minutes, a dull 

 green color, but gradually becomes clearer, and is finally quite lim- 

 pid. On being washed in hot water, the product is usually white, 

 but if found to be not thoroughly bleached, the process is repeated 

 with twenty-three parts of bichromate of potash, and one part of 

 hydrochloric acid. 



Impkoved Aspikatoe. 



The apj)aratus used in the laboratory for drawing gases through 

 liquids by means of a discharge of water from the bottom of a closed 

 jar or bottle which is connected at the top with a pipe conveying the 

 gases, has been modified in form by Prof. A. R. Leeds of Haverford 

 College, Pa., so as to apply the principle of drawing one current by 

 means of another. A water pail is so arranged on a table as to dis- 

 charge its contents into a bucket on the floor by means of a stop cock 

 and tube ; on the top, and in front of the stop cock, is inserted a ver- 

 tical tube connected by India rubber tubing with a wash-bottle or 

 other vessel through which it is to be drawn. When the stop cock is 

 partially opened the descending water draws with it a current of gas, 

 somewhat as air was carried into tuyeres by the water tromp formerly 

 ased in furnaces for reducing iron ore. 



Cdkculio. 

 Experiments made by Benjamin D. Walsh, acting State entom- 

 •ologist of Illinois, have led him to the conclusion that there are two 

 distinct broods of the plum curculio every year, the fii-st of which 

 «omes out in the beetle state in the latitude of Rock Island, from 

 about July 19 to August 4, and the second from August 23 to Sep- 

 tember 28. The first brood is generated by females that have passed 

 the Avinter in the beetle state, and have attacked the early fruit, laying 

 in the more matured fruit the egg from which proceeds the second 

 brood. Tlie second brood of beetles come out late in the same 

 season, iind the females, at all events, if not the males, live through 



