﻿294 



PROCEEDINGS, 



[Dec, 1858, 



depends, as is well known, on the difference of level between the 

 aperture from which the water flows, and that by which the air 

 enters, and as these are on opposite sides of the Aspirator, by- 

 inclining it, this difference of level may be increased or dimin- 

 sbed, or rendered null, and the velocity of the current of air 

 through the apparatus controlled at will. To provide for a still 

 more rapid flow, if desired, there are two apertures in the side of 

 the Aspirator, near t]je aperture in the partition, one forming a 

 communication with the upper compartment — the other with the 

 lower; short tin tubes soldered to these apertures externally 

 permit connection to be established between them by a short 

 flexible tube, as exhibited in the wood cut, through which the 

 water can flow from the upper to the lower compartment, and 

 by compressing more or less this flexible tube, the velocity of 

 flow may be regulated. Proper means must be used to restrain 

 the tendency of the Aspirator to turn over, the water being upper- 

 most. The same means may be used to regulate the inclination 

 of the Aspirator. 



DECEMBER 1st, 1858. 



Vice-President W. W. Smith in the chair. 



Contributions to Library. 

 Boston Society of Natural History presented Proceedings. 

 Vol. vi., Oct. 1858, pp. 385-400. 



DECEMBER 15th, 1858. 

 Vice-President W. Wragg Smith, Esq., in the chair. 



Contributions to Library. 



Die Oberhessichen Gesellschaft fur Natur- und Heilkunde 

 presented Proceedings, 5th and 6th Nos., Oct. 1855 and June 

 1857, accompanied by a letter from the Society's Secretary, 

 soliciting exchange. 



W. Wragg Smith, Esq., read " Notes and Additions to the 

 Flora of the Low Country of South Carolina." * 



* See Note p. 224. 



