some new Objects in Chemical Philosophy. 65 
metallic oxides as belonging to the same class of bodies, and 
the earths as calces which they had not found the means of 
combining with phlogiston, and though Lavoisier insisted 
upon this analogy with his usual sagacity, yet still the alkalies, 
earths, and oxides, have been generally considered as separate 
natural orders. The earths, it has been said, are not precipi- 
tated by the triple prussiates, or by the solutions of galls ; * 
and the alkalies and alkaline earths, are both distinguished by 
their solubility in water ; but if such characters be admitted 
as grounds of distinct classification, the common metals must 
be arranged under many different divisions ; and the more 
the subject is inquired into, the more distinct will the general 
relations of all metallic substances appear. The alkalies and 
alkaline earths combine with prussic acid, and form compounds 
of different degrees of solubility ; and solutions of barytes ( as 
has been shewn by Dr. Henry and M. Guyton,) precipitate 
the triple prussiate of potash ; the power of combination is 
general, but the compounds formed, are soluble in different 
degrees in water. The case is analogous with solutions of galls ; 
these, as I have mentioned in a paper published in the Philoso- 
phical Transactions for 1805, are precipitated by almost all 
neutrosaline solutions ; and they form compounds more or 
less soluble in water, more or less coloured, and differently 
coloured with all salifiable bases. It is needless to dwell upon 
the combinations of the alkalies and earths, with oils, to form 
soaps ; and of the earthy soaps, some are equally insoluble 
with the metallic soaps. The oxide of tin, and other oxides 
abounding in oxygene, approach very near in their general 
characters to zircon, silex, and alumine ; and in habits of 
* Klaproth. Annales de Chimie. Tom. X. p. z 77. 
MDCCCX. K 
