136 



VENTILATION FOR THE LABORATORY TABLE. 



vided with the necessary supply and waste pipe. Be- 

 sides rapid filtration, the usual object sought by the use 

 of this apparatus, the writer lias found it to be an ad- 

 mirable means for aspiration in all the usual applications 

 of the process. Iu addition to these purposes he has 

 also employed the same instrument for carrying off nox- 

 ious vapors from the laboratory table in the process of 

 evaporation. 



To fit the aspirator for general use it is mounted over 

 a small sink at one corner of the work table, with con- 

 nections shown in Fig. 1. A small glass tube, t, joined 



^t 



1. 2. 3. 



to the exhaust pipe by rubber tubing, 7/, jjasses through 

 the air tight cork of an eight ounce wide mouth bottle. 

 A larger tube, c, reaches nearly to the bottom of this 

 bottle. The end, a, of another tube is drawn down to 

 proper size to be thrust into the outer end of this 

 tube, c, through a piece of rubber tubing stretched over 

 their junction. By this means an air tight but flexi- 

 ble joint is secured through which fluids may flow with- 

 out contact with the rubber. This tube is supported 

 against the back of the table by a tin clasp, d, through 

 which it passes loosely. The end, b, is bent forward and 

 carries a short piece of rubber tube by which connection 



is made with whatever apparatus is to be exhausted. 



ss 



