288 



SCIENCE 



[Vol. LVI, No. 1445 



the bottom of the large test tube is a hole M and 

 over it is snugly fitted a layer of glass wool L. 

 Into B the stopper E-E is placed, through 

 which passes a smaller test tube C. This tube 

 also has a small hole at the bottom K, and is 

 fitted at the top with a stopper F-F through 

 which passes a delivery tube fitted with stop- 

 cock 0. 



The large test tube B in stopper D-D should 

 fit especially tight as it is not to be removed 

 from the stopper. E-E should fit more loosely 

 as it may be removed at will. 



The bottle A is the reservoir for the acid /. 

 The tube B is a chamber for holding tube C. 

 C contains the zinc, iix)n sulfide, marble, 

 peroxide, bleaching lime or fused ammonium 

 chloride, etc. (which should, of course, be in 

 lumps) with which the acid acts. A rack of 

 i:ubes filled with different reagents and fitted 

 with stoppers the same size as E-E afford a 

 ready source for each gas, or tube C may be 

 dumped and filled with a different reagent as 

 desired. 



Pinch cocks may be used instead of glass, or 

 nearly any preferable type might be substi- 

 tuted. 



Operation 

 Tube Cj containing marble, zinc or whatever 

 substance is required, J, and fitted with stoppers 

 E-E and F-F and tube G, cock of which is 

 closed, is introduced into the chamber B. The 

 ail' or gas in C prevents the acid from entering. 

 To operate, open N and 0. Close N after 

 acid has run into C through M and K so that 

 the acid will not be forced out of C. Pass the 

 delivery tube into the test tube P or collect in 

 any other fashion. 



To stop the generation, see that N is open. 

 Close 0. The gas will force the acid out of C, 

 and out of B. The apparatus may then be set 

 away for another time, or if preferred C may 

 be removed in a comparatively dry condition 

 both inside and outside after closing N so that 

 the chamber B will remain empty while C is 

 being removed. 



The acid need not be changed except when 

 any impurities it contains might interfere with 

 the test to be run, or when it has eventually 

 become exhausted. To supply new acid simply 

 remove the stopper D-D which takes with it all 



the fixtures, empty the jar A and refill. Re- 

 place the stopper, and all is ready for use. 



Arthur P. Harrison 

 BuKEAU OF Plant Industry, 



U. S. Depabtment op Agriculture 



THE OHIO ACADEMY OF SCIENCE 



The thirty-second annual meeting of the 

 Ohio Academy of Science was held at Ohio 

 State University, Columbus, April 14 and 15, 

 1922, under the presidency of Professor Ray- 

 mond C. Osburn, of Ohio State University. 

 Eighty-seven members were registered as in 

 attendance; forty-six new members were elect- 

 ed. 



The usual geological excursion was post- 

 poned until June 3 and 4, and took the form 

 of a joint field meeting, on invitation of the 

 geologists of the Michigan Academy of Science, 

 for the study of the glacial geology and 

 Silurian rocks of southeastern Michigan and 

 adjoining portions of Ontario. The party was 

 under the leadership of Mr. Frank Leverett, of 

 the University of Michigan, and Professor 

 W. H. Sherzer, of the Michigan State Normal 

 College. Professor J. E. Carman, of the Ohio 

 State University, collaborated in directing the 

 investigations at certain localities. 



The Connnittee on State Parks and Con- 

 servation reported progress in the listing of 

 areas suitable for preservation. Director Ta- 

 ber, of the State Department of Agriculture, 

 addressed the academy on the game preserves 

 owned or leased by the state. The academy 

 expressed its formal approval of the estab- 

 lishment of a state commission, including scien- 

 tific representation, to advise in the acquisition 

 of state parks and preserves and in their 

 regulation to secure the maximum recreation- 

 al, scenic and scientific returns. 



The trustees reported the twenty-fifth an- 

 nual gift of two hundred and fifty dollai-s from 

 Mr. Emei-son MeMillin, of New York City, 

 in furtherance of the research work of the 

 academy. A resolution of thanks and the 

 birthday greetings of the academy were sent 

 to Mr. MeMillin by night letter, to, reach him 

 on April 16, his seventy-eighth birthday. (The 

 death of Mr. MeMillin on May 31 has already 

 been reported in Science. He was a member 



