230 
so many periodical publications, and 
edited them under the title of ‘‘ Con- 
tributions to the Chemical Knowledge 
of Mineral Bodies.” Of this work, 
which must always be a classical pro- 
duction in chemical literature, six 
volumes had appeared by the year 
1815 ; containing, in no fewer than 207 
treatises, the most valuable part of all 
that Klaproth had done for chemistry 
and mineralogy. 
Besides Klaproth’s own printed 
works, he superintended a new edition 
of Gren’s Manual of Chemistry, with 
respect to which, however, he did not 
seek to earn so much merit by what he 
added, as by what he took away and 
corrected. But the part which he tock 
in the Chemical Vocabulary, which 
was edited under his own name, and 
that of Wolff, was of great importance. 
Passing by the numberless small ex- 
pedients which Klaproth devised for 
procuring a more unmixed deposition 
and separation of all kinds of matters, 
we only notice at present that he en- 
riched experimental chemistry with 
two new methods of analysis, which 
are unlimitedin their applications. The 
first of these was the complete resolu- 
tion of the hardest minerals by means 
of fluid caustic alkali, instead of the 
former treatment with dry caustic 
alkali, which had introduced the use of 
silver crucibles and saucers into expe- 
yimental chemistry. The complete 
resolution of the hardest stones, by this 
method of analysis, has enabled us to 
ascertain, with extreme accuracy, the 
quantity of earths, oxydes, metals, and 
even of acids, which mincrals contain. 
Exact analyses of this kind remain 
sure for ever, and are of importance to 
the science, independent of any disco- 
veries which may be made, respecting 
the particular nature of the substances 
mentioned. As, for stance, the capa- 
bility of being decomposed, which was 
afterwards discovered to belong to the 
earths, makes not one cypher incorrect 
or superfluous in such analysis. The 
advantage of this method is particu- 
larly evident in the decomposition of 
corundum, or diamond-spar. As Kla- 
proth first attempted the analysis of 
these bodies by the former method of 
‘decomposition, he found a considera- 
ble remainder of matter unaccounted 
for. On the suspicion, which he then 
expressed, that this remainder might 
perhaps beanew, and yet undiscovered 
earth, many compilers of school-books 
were in a hurry to admit the earth of 
Biographical Account of Martin Henry Klaproth. 
[Oct. 1, 
corundum into the list of the simple 
earths. But, when Klaproth repeated 
the analysis by means of the liquid 
alkali, he found, that this substance 
was one of the many compositions of 
siliceous and argillaceous earths which 
had not previously been known, and 
which m former analyses had some- 
times been referred to the one kind of 
earth, and at other times to the other. 
In the same manner, the chemists of 
England gave an account of a species 
of sand, which had been brought from 
New Holland, as a new earth; but 
Klaproth shewed, by his new method of 
analysis, that this body also, which 
had already been introduged into intro- 
ductory treatises, under the name of 
“the Austral Earth,” was nothing but 
an intimate mixture of siliceous and 
argillaceous earth. Indeed, the first 
analyses that can be considered as 
certain, are those which have been un- 
dertaken on this plan. Hence, by this 
discovery, almost all the more early 
analyses have lost their value. Of 
what inestimable moment such a dis- 
covery must be, not merely to experi- 
mental chemistry, but to the whole of 
the science of nature, even although 
Klaproth had not discovered by means 
of it a single unknown body, does not 
require to be more particularly stated. 
The great care which Klaproth em- 
ployed in securing the neatness of his 
experiments, was not the least of his 
merits, not only because the great con- 
fidence which his labours deserve rests 
chiefly upon this circumstance, but 
also because in this he was a pattern 
to all practical chemists. ‘Yo this qua- 
lity must be referred the attention 
which he bestowed on his instruments. 
When he had to do with very hard 
minerals, he used a mortar of flint, but 
he previously analysed it, and did not 
neglect the small and scarcely percep- 
tible increase of weight whiclr the mat- 
ter under examination derived from 
continued rubbing, and, according to 
the differences of the substances that 
were before him, it was by no meansa 
matter of little moment in his estima- 
tion, whether the pounding, which was 
always continued till the body was re- 
duced to an impalpable powder, was 
conducted in vessels of flint, of calce- 
dony, of glass, of serpentine, or of me- 
tal. And, when he operated with fire, 
he always selected his vessels, whether 
of earthenware, of glass, of graphite, of 
iron, of silver, or of platina, upon fixed 
principles, and shewed more ae 
than 
