A SIMPLE APPARATUS FOR AKRATlNi; LlOl ID 

 SOLUTIONS. 



In studying the effect of dilute and concent 

 sea water on marine algas it became necessar)- 1 

 tions in order to keep them fresh. For thi 

 simple piece of apparatus was devised. The aj 

 slowly to concentrate or dilute the solutions a; 

 them. It has now been in continuous operat 

 months and has proved to be so effective, t 

 care, and to be so easily made, that a brief des 

 be useful to others. 



The general structure of the apparatus will 

 stood by referring to the accompanying figure; 

 necessary then to discuss a few details of its 

 principles on which its operation de}K'tKls. 



The aerating tubes used in the experiment^ 

 are 90 cm. long and 4.5 mr^ 



The capillary siphon is 0.75 nim. in diame ci , 

 the culture jar is 27 cm. deep. It will rcadil 

 since the aerating tube is much larger than the ( 

 if both are to be constantly full the solution n 

 more slowly in the tube than in the sii)hon. 



Owing to the action of gravitation, however, tl 

 solution tends to accelerate as it falls, and tlu 

 flow faster in the aerating tube than in the sipl" 

 solution in the tube as it flows through the 

 broken into very short col s sti rat 1 1 



