REDUCTION OF CHEMISTRY TO MATHEMATICAL PRINCIPLES. 537 
Section B.— CHEMISTRY AND 
MINERALOGY. 
Mr. Exley’fe; paper on the reduction of 
Chemistry to mathematical principles, 
was the first read. Mr. Exley commen- 
ced with a division of atoms, into what 
he denominated the tenacious, the ethe~ 
real, thQ electrical ; the first being 
distinguished by posessing the great- 
est, the last by enjoying the least absolute 
force, while in this particular the electri- 
cal occupied an intermediate position. 
In reference to these atoms, two propo- 
sitions were then laid down, the first of 
which affirmed the atoms to attract each 
other according to the inverse square of 
the distance up to a particular point, 
when the attraction was converted into 
repulsion ; the second, that dissimilar 
atoms differ in the relative energies of 
their attractive and repulsive forces, 
though these forces vary according to 
the same law. Mr. Exley having compar- 
ed his views with those of Newton and 
Boscovich, and pointed out the particu- 
lars in which they differed, proceeded 
to state the grounds which led him to 
conclude that water was a ternary, not a 
binary compound ; or, in other words, 
that sixteen, not eight, was the atomic 
weight of oxygen. 
Having disposed of these preli- 
minary topics, Mr. Exley entered upon 
the developement of his views in the 
form of a series of sixteen propo- 
sitions. It is scarcely necessary to 
say, that this part of his paper does 
not admit of popular explanation; 
and it would be presumptuous in 
any individual to undertake the task, 
who was not deeply versed in the 
mathematical sciences, and who had 
not had the advantage, not only of per- 
using, but of studying the profound re- 
searches of Mr. Exley. We have, how- 
ever, no hesitation in asserting that 
these researches are deserving of ma- 
ture consideration. According to New- 
ton, before a hypothesis is admitted, it 
must be proved true, and adequate to 
the explanation of phenomena. The 
former test is sometimes very difficult 
of application, and would be particular- 
ly so in the present instance. But, as 
respects the latter criterion, it must be 
admitted to pronounce in favour of Mr. 
Exley’s theoretical postulates; for, by 
following these out, and applying to 
them mathematical reasoning, he is en- 
abled to anticipate and explain a varie- 
ty of the most important facts in che- 
mistry and general physics. Thus, he 
deduces with facility from his princi- 
ples the ordinary laws of chemical com- 
bination, Gay-Lussac’s law of volumes, 
and even the variations of volume, 
which the gases are known to experi- 
ence when submitted to various tem- 
peratures and pressures. But the most 
striking evidence of the truth of his 
theorems, adduced by Mr. Exley, re- 
mains to be mentioned. He has calcu- 
lated by his abstract methods the spe- 
cific gravities of fifty-seven substances, 
supposed in the gaseous state, (some, 
such as alcohol, oil of turpentine and 
camphor, being compounds of an ex- 
tremely complex nature,) and found 
the results to correspond as closely as 
could in such investigations be expect- 
ed, with those obtained by direct ex- 
perimental means. Doctors Dalton 
and Thomson of Glasgow, as well as 
other competent judges, bore testimo- 
ny to the ingenuity and talent shown 
in Mr, Exley’s paper. 
Mr. Babbage next exhibited a ther- 
mometer, recently discovered in Italy, 
and supposed to be one of those origi- 
nally manufactured for the Societa del 
Cimento. It appeared to be filled with 
alcohol. The bulb was spherical, and 
the stem was divided into fifty equal 
parts by beads attached to it by fusion 
at equal distances. These instruments, 
as is well known, being graduated 
without reference to fixed points, do 
not give indications comparable with 
those of the modern thermometer. Li- 
bri, it is generally understood, and the 
circumstance was stated by Professor 
Babbage, has attempted the interpre- 
tation of the scale of these instruments, 
partly by a comparison with each other 
of ancient and modern meteorological 
registers, and partly by taking with 
them the temperatures of certain tepid 
waters in the Pyrennees, which had 
been previously examined by the Flo- 
rentine Academicians. Dr. Daubeny 
observed upon the inaccuracy of the 
latter method, as that springs undoubt- 
edly undergo, in process of time very 
considerable changes of temperature. 
An essay on Gaseous Interference, 
by Dr. Charles Henry, was next read, 
— It is universally known to chemists, 
that if oxygen and hydrogen be mixed, 
and brought into contact with metallic 
platinum in the state of wire or foil, or 
