ON MimiATIC ANO bXIMtI»Il*riC ACIB. * tlQ 



EaTtli or moon ; and the striking uniformity of all the 



masses, that have fiillen at different places and times (which 



indicates a common origin) does not, if we reason from ' 



the analogy of the planetary system, altogether agree with 



the supposition, that such bodies are satellites of the 



earth. 



VIL 



On Muriatic and Oximnriatic acid, in Reply to Mr. Daltok. 



In a Leterfrom a Correspondent. 



To Mr, NICHOLSON. 

 SIR, 



^Y object in " the remarks on the nature of potassium Remarks on 



and sodium, in answer to Mr. Dalton,'* which you did me ^Xm.""*"* 

 the honour to publish in your number for January last, was 

 not so much to advance any thing new, as to state fairly tlie 

 arguments used by Mr. Dalton to prove those bodies to 

 be hidrurets; and the facts, which induced Mr. Davy to 

 place them in the class of metals. It is not my intention to 

 pursue that subject farther in this communication, as I feel 

 satisfied, that even the splendid talents of Mr. Dalton, 

 (should he honour my animadversions with a reply) will not ..\- 



be sufficient to controvert the deductions drawn by Mr. 

 Davy from his experiments on these bodies — Indeed I should 

 not have troubljcd you now, had not Mr. Dalton called on 

 me, to explain my data, and mode of calculation, respecting 

 the muriatic acid, and oximuriatic gasses. As to my data 

 behig defective, and the principles of mi/ calculations ttni«- Principles of ; 

 telligihle to Mr. Dalton, I can only say, that I have taken tl'ewriter»8 

 the former from Dr. Henry's Elements of Experimental 

 Chemistry, 6th edition, 1810, (a work dedicated to Mr. 

 Dalton) where in a table at p. 499» vol. II, I find the spe- 

 cific gravity of muriatic acid gas given as 1*430, according 

 to Brisson—- and 'pSQ according to Kirwan, Here is so great 

 a ditference, that, not knowing which to choose, I referred 



to * '" ' 



