ACCUM’S SYSTEM OF THEORETICAL AND PRACTICAL CHEMISTRY. 
is very simple and nnembarrassed. The 
two first volumes are occupied with the 
chemical analysis of all the solids and 
fluids of animal bodies, including a his- 
tory of every important series of experi- 
ments that have been made in modern 
times, and are scattered through jour- 
nals, elementary works, miscellanies, &c. 
in different languages. Of these, the 
German authorities have been examined 
with considerable minuteness, and indeed 
the general execution of the work some- 
what reminds us of German industry and 
of German exhaustiveness in selection. 
Art. IV. 4 System of Theoretical and Practical Chemistry. 
923 
The third volume examines the che- 
mical changes that take place in the liv- 
ing body, of which the subjects of animal 
heat and respiration stand conspicuous, 
and are treated with peculiar care. 
As the author only aims at accuracy 
in compilation, and clearness in descrip- 
tion, it would be unfair to expect a dif- 
ferent excellence; his task is well per- 
formed, and we doubt not that public 
approbation will bear testimony to its 
utility. 
In Two Volumes, with ~ 
‘Plates. By Frevericx Accum, Teacher of Practical Chemistry, Pharmacy, and 
Mineralogy, and 
pp- 800. 
CHEMISTRY is now become a sub- 
ject of such vast extent, that a familiar 
acquaintance with every branch of this 
science is hardly to be expected from any 
individual, nor have we yet seen a single 
system which has any real claim to be 
considered as perfect. In some the 
pneumatic part is chiefly insisted on, in 
others the metallic substances are the 
favourite objects, others again are prin- 
cipally valuable for the chemistry of ve- 
getable and animal bodies. The forte of 
some authors consists in a clear and per- 
spicuous account of the prevailing theo- 
ries and opinions, while others endea- 
vour to render themselves useful to the 
operating chemist. 
The work before us is a very conve- 
nient manual for a lecturer, and will be 
found of equal use by the student who 
wishes to repeat in his own laboratory 
some of the most striking and beautiful 
experiments of modern chemistry. ‘The 
first volume, which is principally occu- 
pied by caloric and the gasses, is the 
most useful, and contains a multitude of 
well selected experiments which are not 
generally known. ‘The second volume, 
which comprehends the metals, earths, 
acids, alkalies, compound salts, vegetable 
and animal substances, &c. is much too 
crowded to be of any great value. The 
general plan which Mr. Accum has 
adopted, with regard to those sul* ances 
that he treats of the most at length, isto 
appropriate a chapter to each, which he 
divides into two sections; in the first he 
enumerates the characters, and the seve- 
ral modes of obtaining the substance in 
a pure state, and the second is appro- 
priated to experimental proofs of the va- 
Chemical Operator in the Royal Institution of Great Britain. 8vo, 
rious properties with the:rationale of the - 
more complicated processes. 
Asa specimen of the work we shall 
select part of the second section con- . 
cerning phosphorated hydrogen gas. 
‘* EXPERIMENT TI. * 
*© Phasphorated hydrogen gas takes fire 0% 
coming into contact with atmospheric air. 
«<'This may be evinced by charging a smalk 
retort with potash, phosphorus and water, 
in the manner mentioned before, applymg 
heatand dipping the mouth of the retort into 
a bason of water The bubbles of the air, 
which come from the retort and pass through 
the water, will burst with a slight explosion, 
and produce flashes of fire in the cireumam- 
bient air. A circular dense white smoke 
rises horizontally like a ring, enlarging itself 
continually, and forming a sort of corona 
extremely beautiful if the air be perfectly. 
tranquil, 
<The finest effect is produced when the 
flashes of gas succeed eat other but slowly. 
** Rationale. We have noticed before, that 
phosporated hydrogen gas is nothing but hy- 
drogen gas holding phosphorus in solution. 
When this gaseous fluid is presented to the 
atmospheric air or oxygen gas, the minutely 
divided phosphorus rapidly attracts, oxygen 
and inles: setting fire at the same time to 
the hydrogen gas in contact with atmospheric 
air, and hence phosphoric acid and water are 
formed. ° 
««' The circular crown of white smoke 
which rises after the explosion of the gas, 
originates from the coat of water which er- 
veloped the bubble of the gas; this water, 
together with what is formed during the ex- 
losion, is suddenly converted into vapour, 
it unites to the phosphoric acid produced, 
and thus constitutes the circular crown of 
smoke which rises in a ring. aig. 
«« If a wider-mouthed phial be filled wit 
phosphorated hydrogen gas, and left in that 
