THE 



AMERICAN 



JOURNAL OF SCIENCE, &c. 



Art. I. — Experiments for acertaining the best method of ohtaining 

 and preserving Potassium ; by L. D. Gale, M. D. Assistant to 

 the Professor of Chemistry in the College of Physicians and Sur- 

 geons, City of New York, Sept. 1830. 



TO PROFESSOR SILLIMAN. 



Dear Sir — I take the liberty of sending you an account of a 

 course of experiments made in the Laboratory of the College of Phy- 

 sicians, during the past spring and summer on the preparation of Po- 

 tassium. My chief object in these experiments was, 1st. to acertain 

 the best proportions of the materials to be used ; 2d. the most eco- 

 nomical receptacle for condensing the metallic vapor ; 3d. the best 

 means of preserving the metal so as to exhibit its high metallic lustre. 

 The apparatus generally (described in the books on Chemistry, is 

 much too comphcated and expensive to admit of general use : yet 

 with the simplest apparatus, from the numerous sources of failure no 

 tyro in the profession I am confident, can manufacture potassium 

 without first serving an apprenticeship. Even the chemist who is 

 well experienced in the more common manipulations, will often suf- 

 fer the mortification of a complete failure, because he is not familiarly 

 and practically acquainted with all the circumstances requisite to ob- 

 tain success. Hence this metal though it may be afforded at a low- 

 er price than it now bears in the market, will probably never be sold 

 even at wholesale, for less than twelve or fifteen dollars the ounce. 

 I made eight experiments in which three retorts were burnt through 

 six pounds of potassa consumed, and about four ounces of the me- 

 tal obtained. During the first operation, Professor Torrey* was pres- 



* I lake this opportunity thus pubhcly to ackriovvleilge my obli.o-ation to Professor 

 Torrey, for the many useful hints given me on this occasion. 



Vol. XIX.— No. 2. 27 



