The sun., 1900-12-30


detail as to the method and arguments
necessary-suiiice it to say that the
Hungarian physicist Eotv0s was the first
| TO indicate the direction OF research, and
that Ramsay and Shields succeeded in
| proving that the complexity OF the mole
| cules OF most liquids Is not greater than
that Of the gases which they form on being
vaporized; and also that certain liquids. @. g..
water the alcohols and other liquids. are
| more or less associated |. g.. their mole
| cules occur in compexes OF two. three. four
or more, and a. the temperature is raised
| the complexity of molecular structure
| diminishes.
As regards the molecular complexity OF
| solids. nothing definite Is known. and.
moreover. there appears to be no method
capable Of revealing it,
RLECTRo-CHEMCAL THEORY.
While the researches OF which a short
account has now been given have led to
knowledge regarding the nature Of mole
cules, the structure Of the molecule has
| excited interest since the early years OF
the century. and It's investigation has led
composition of acidifed water by an electric
current, discovered by Nicholson and
Carlisle and of salts into bases" and
acids" by Berzelius and Hisinger in 1903
led to the belief that close connection
exists between electric energy or. as It
was then termed electric force" and the
affinity which holds the constituents OF
chemical compounds in combination In
1907 Davy propounded the theory that all
compounds consist Of two portions. one
electro positive and the other electro
negative. This idea was the result OF
experiments on the behavior Of substances
such. for example. n copper and sulphur
If portions OF these elements be insulated
and then brought into contact they become
oppositey electrified. The degree of cleo
trilcation is intensified by rise OF tenn
perature until when combination ensues
the electrihcation vanishes. Combination.
therefore. according to Davy. is concur
rent with the equalization Of potentials. In
1912, Berzelius brought forward an electro
chemical theory which for the following
twenty years was generally accepted. His
primary assumption was that the atoms OF
clements, or, in certain cases. groups OF
atoms. are themselves electrified; that each
atom. or group of atoms. possesses two
poles. one positive, the other negative: that
the electrihcation Of one Of these poles pre-
dominates over that OF the other. so that
the atom or group is itself. IA whole,
electro positive, or electromagnetic; that
combination ensuel between such OPP
postely electrified bodies by the neutral-
zation. partial or complete. Of their electric
charges: and. lastly. that the polarity Of
an element or group could be determined
by noting whether the element or group
separated at the positive or at the negative
pole of the Calvanc battery, or electrolysis.
For Berzelius. oxygen was the most electro
negative and potassium the most electro
positive Of the elements. the bridge between
the "non-metals" and the metals" being
hydrogen. which. with nitrogen. forms a
basic or elcctro-positive group, while with
chlorine. &c. IL forms electromagnetic
groups. The fact that an electric current
splits compounds in solution into two por-
tons led Berzelius To devise his dual
istic" system. which involved the assump-
ton that all compounds consist OF two
portions. one electro positive, the other
electromagnetic. Thus. sulphate Of mag
nesium and potassium was to be regarded
as composed of electro-positive potassium
sulphate in combination with electro
negative magnesium sulphate; the former
in It's turn consisted Of electromagnetic
sulphur trioxide 500 in combination
with electro-positive oxide OF potassium
KgO): while each Of theee proximate con-
sttuents of potassium sulphate were them
selves composed Of the electro-negatlve
oxygen in combination with electro-posi-
tive sulphur. or potassium. On contrast
ing sulphur with potassium. however.
the former was considered more electro
negative than the latter; so that the group
sos as a whole was electro negative, while
no was electro-positive. The symbols
given above. which are still In universal
use, were also devised by Ber2eius for the
purpose of illustrating and emphasizing
his views. These views, however. met
with little acceptance az the time in Eng
land.
OLD THEORIES LOSE GROUND.
Lavoisiers idea that oxygen was the
necessary constituent Of all acids began
about this time to lose ground. For Davy
had proved the elementary nature Of
chlorine; and hydrochlorio acid. one Of
the strongest was thus seen TO contain no
oxygen, and Davy expressed tho view.
founded on his observation. that iodic
acid" l,OJ, was devoid Of acid properties.
until dissolved in water, and that the es-
sential constituent Of all acids was hydro
gen, not oxygen. The bearing Of this
theory on the duallstic theory Is. that while.
g. g.. suphuric acid was regarded by Ber-
zelius Us sos. containing no hydrogen,
and was supposed to be separated as such
at the positive pole of battery. Davys
suggestion led to the opposite conclusion
that the formula of sulphuric acid is H,SO..
and that by the current 1t is resolved into
IIa and SO. Faradays electrolyuc law,
that when current is passed through cleo
trolytes in solution the elements are liber-
ated In quantities proportional to their
equivalents. led TO the abandonment OF
Al. aba