Che)nical Science. 



385 



furnished with feet, for then there is more space for the fluid. 

 A series of glass receivers, contracted at top in the usual way, 

 form the other part of the apparatus. Their number and size is 

 to be such, that one will go between each glass jar, and they 

 are to be connected together by the necks air tight, in a way 

 that, when put down among the glass jars, each shall take its 

 proper place ; a trumpet-formed tube is to be fixed in the midst' 

 of these receivers, its wide termination being destined for the 

 inner jar, and the narrow end to pass upwards through the 

 necks of the receivers, and to form the only aperture through 

 them ; on this is fixed globular receiver, to which a retort 

 generating gas or any other apparatus, may be fixed. When 

 used, as for instance in the production of 

 muriatic acid, water is putinto the jars, 

 and the receivers dropped down until 

 their edges dip some way into the water, 

 then muriatic acid gas being made to enter 

 above, any impurities it carries over are 

 deposited in the balloon, and the gas 

 passes down the trumpet tube, and is ab- 

 sorbed by the fluid beneath. When that 

 portion of the fluid is saturated, the gas by 

 its pressure depresses the solution, and 

 escaping into the first receiver, gets round 

 the edge of the jar, and comes in contact with the water on its 

 outside in the second jar; it becomes also saturated, and then 

 the gas passes into the second receiver, and so on. 



The form and the shape of this apparatus are easily varied, 

 they have been made of porcelain and stone ware, they have 

 also been made square and oblong. Dr. Hare, has found them so 

 effectual as to produce a strong solution of muriatic acid in the 

 central jar, when the fluid in the third and external jar has not 

 been at all acid. — Silliman's Journal, Vol. I. p. 410. 



25. New Method of preparing tlie Purple of Cassius.~The 

 Count de Maistre says, that placing a sequin in contact with 

 mercury at one of its surfaces, and twenty-four hours after 



