THE 
PHILOSOPHICAL MAGAZINE 
AND JOURNAL: 
COMPREHENDING 
THE VARIOUS BRANCHES OF SCIENCE, 
THE LIBERAL AND FINE ARTS, 
GEOLOGY, 
AGRICULTURE, 
MANUFACTURES, AND COMMERCE, 
BY ALEXANDER TILLOCH, LL.D. 
M.R.1I.A. M.G.S. M.A.S. F.S.A. EDIN. AND PERTH} CORRESPONDING MEMBER 
OF THE ROYAL ACADEMY OF SCIENCES, MUNICH 3; AND OF THE ACADEMY 
OF SCIENCES, LITERATURE AND ARTS, LEGHORN, &c. &c. &c. 
* Nec aranearum sane textus ideo melior quia ex se fila gignunt, nec noster yilior quia 
ex alienis libamus ut apes,’ Just. Lies. Monit. Polit. lib, i, cap. 1. 
‘ 
VOL. LVIU. ‘ & 
For JULY, AUGUST, SEPTEMBER, OCTOBER, NOVEMBER, 
and DECEMBER, 1821. 
iS oemueiateneeeness, ©... aceon 
> 
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