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May 28, 1885 | 
CHEMICAL NOTES 
IN a paper communicated by Prof. Mendeleeff to the last issue 
of the Hournal of the Russian Chemical Society, being a reply 
to M. Avenarius, the Professor makes a very interesting com- 
parison between his own formula of dilatation of liquids and the 
logarithmic formula of Waterston, supported in Russia by his 
opponent, M. Avenarius. He shows by analysis why both for- 
mulas express with sufficient approximation the expansion of 
ether within the limits of 0° and 104°, the observations beyond 
that limit having to be left aside until we have a more accurate 
knowledge of the laws of expansion of this substance at higher 
temperatures and under higher pressures. He demonstrates, 
moreover, that the logarithmic formula is as inapplicable to 
water as his own ; and, developing both formulas into series, 
he shows why his own simpler formula ought to be considered 
as a first approximation to the law of dilatation of liquids 
until the true law is discovered. Though polemic in its first 
part, the paper is a masterly piece of scientific treatment of the 
controversy about so important a question. 
FoLLowINc on the lines laid down by Mr. H. B. Dixon in 
his experiments on the combustion of carbonic oxide in dry and 
in moist oxygen, Mr. H. Brereton Baker has recently described 
some very interesting results regarding the combustion of phos- 
phorus and carbon in oxygen. When the elements in question 
were heated in oxygen which had been kept in contact with 
phosphorus pentoxide for some weeks, combustion occurred only 
to a very limited extent. The presence of a small quantity of 
water-vapour seems to be needed in order to start the com- 
bustion (C. S. Journal, Trans., 1885, 349). 
THE influence of the relative masses of the reacting bodies on 
chemical changes has of late years received a good deal of atten- 
tion. Urech has discussed the well-established data regarding 
the influence of dilution, and of the presence of excess of one 
or other ingredient, on chemical reactions (Ber., xviii. 94). He 
points out that the diluent may act both physically and chemi- 
cally. When it acts altogether as a diluent it does not, according 
to Urech, affect the rate of the chemical operation. Excess of 
either reacting body appears always to exert an influence on the 
rate of change. ‘The causes of the variations in the rate of 
chemical change are probably very complicated ; even the shape 
aaa of the containing vessel may exert an appreciable 
effect. 
EXPERIMENTS are described by M. J. Thoulet (Compt. Rend., 
xcix. 1072) on the effect of immersing various solid bodies in 
saline solutions, e.g. marble, quartz, &c., in aqueous solutions 
of sodium or barium chloride. In each case a portion of the 
dissolved salt was precipitated on the surface of the immersd 
solid. The conclusion is drawn that there is an attraction 
between the dissolved salt and the solid immersed, and that the 
amount of attraction is proportional to the surface of the solid. 
SoME time ago Mr. Bayley showed that when drops of various 
solutions are allowed to fall on to filter-paper, the salt which 
was in solution in many cases remains in the centre, and a water- 
ring extends around it. Mr. J. U. Lloyd has extended these 
observations (Chem. Nezws, li. 51). He has observed the distances 
to which various substances in aqueous solutions extend on 
pieces of blotting paper, dipped into the solutions, before they 
are left behind by the water. Great differences were noticed in 
the length to which different salts thus travelled. Mixtures of 
salts were also examined; in some cases one salt passes on, 
leaving the other completely behind. Thus a solution of quinine 
and berberine sulphates was separated by the method described ; 
the former salt passed on through the paper after the progress of 
the latter had quite ceased. Dilute sulphuric acid behaved 
similarly ; pure water alone passed onwards. In the case of 
simple salts dissolved in water, the rule appears to be that the 
more dilute the solution, the quicker is the separation into salt 
and water. 
CHEMIS1's are beginning to realise that the structural formulz 
they have so long rezarded as final expressions are, after all, 
very imperfect representations of chemical operations. The 
molecule of a compound has been treated as a structure built up 
of atoms ; in their anxiety to learn the relations of these atoms 
chemists have almost forgotten that the molecule is itself a whole, 
Attention has of late been recall<d to this aspect of molecular 
formule. Hartley’s researches on ‘‘the relation between the 
molecular structure of carbon compounds and their absorption 
spectra ” have led to results of much interest in this direction. In 
NATURE 
87 
a paper communicated to the Chemical Society on May 7, 
Hartley brought forward a series of facts which lead to the 
conclusion that ‘‘ molecules vibrate as wholes or units, and the 
fundamental vibrations give rise to secondary vibrations which 
stand in no obvious relation to the chemical constituents of the 
molecule, whether these be atoms or smaller molecules. Hence 
it appears that a molecule is a distinct and individual particle 
which cannot be truly represented by our usual chemical formulz, 
since those only symbolise certain chemical reactions and physi- 
cal properties, and fail to express any relations between physical 
and chemical properties.” 
Nasini (4¢ti d. Acc. d. Lincet Rdct., 1885, 74) has been pur- 
suing his inquiries regarding the ‘‘ atomic refraction” of sulphur 
in various compounds, and has obtained results which lead him 
to conclude that the variations in the refraction-equivalents of 
sulphur compounds cannot be explained by the ordinary struc- 
tural formulze employed in chemistry. These variations appear 
to be connected neither with the valency of the sulphur-atom in 
the different molecules, nor with the nature of the other atoms 
which are associated with the atoms of sulphur. Changes in 
the structure of sulphur-containing molecules seem to be ac- 
companied by changes in the refraction-equivalents of these 
molecules, but these changes cannot be regarded as due to 
variations in the valency, or arrangement, of the atom of sulphur 
they must rather be attributed to some cause which affects the 
molecule as a whole. 
WE notice a very interesting and important discussion raised 
in the Yournal of the Russian Chemical Society (vol. xvii. 3) 
by Prof. A. Butleroff, with regard to Prof. Menshutkin’s ex- 
planation of isomerism by ‘‘ substitution.” M. Butleroff very ably 
advocates the’ theory of ‘‘structure,” ¢.e. of a combination of 
molecules, instead of atoms, and of compound molecules with 
atoms. The chief principles advocated by the author appear as 
follow :—We are right in speaking, as of a real thing, about 
mutual chemical relations between atoms and molecules ; and it 
is only by admitting some differences in these relations (some 
differences in the manner of their ‘‘union”’) that we can explain 
the phenomena of isomerism. These differences are constant, 
permanent to the molecules; they are their inseparable charac- 
teristic attributes. These principles being admitted, the author 
deduces from them the following conclusions :—‘‘ (1) The scheme 
of substitution (advocated by Prof. Menshutkin) permits rightly 
to foresee and formulate isomerides only when the structure is 
supposed known ; (2) it requires auxiliary hypotheses, and it is 
devoid of simplicity and lucidity ; (3) the fundamental ideas, both 
of the theory of substitution as applied to organic bodies and 
of that of chemical structure, are the same ; therefore the former 
gives nothing new which is not given by the latter; (4) being 
narrower and more one-sided, when applied to isomerism in 
organic bodies, the former—if it be applied alone—does not 
in many instances foretell certain phenomena which are simply 
and easily foreseen by the theory of chemical structure.” 
GEOGRAPHICAL NOTES 
A BriTIsH Mission from India is being sent to Cashmere in 
charge of Col. Lockhart, who is accompanied by Major Wood- 
thorpe, Capt. Barrow, and Dr. Giles, and an escort consisting of 
two non-commissioned officers and twenty men. The chief 
object of the Mission is to obtain further geographical informa- 
tion concerning the countries on the northern and western 
frontiers of Cashmere. It will visit Chitral and the neighbour- 
hood of that place, and will be absent for several months. 
M. Leonarvo Fé£a, of the Museum of Natural History at 
Genoa, has been despatched by the Italian Government on a 
scientific journey to Burmah. He is to make zoological collec- 
tions, and also to make various scientific observations. He was 
provided with letters to the Burmese Government at Mandalay. 
The Geographical Society of Rome has received from Capt. 
Molinari reports of two journeys which he has recently made in 
the Shan States. 
AT the usual meeting of the Dutch Aardrijkskundig 
Genootschap on April 18, a general view of those parts of New 
Guinea was given to which the Society wishes to send an expe- 
dition. The Government has promised a grant not exceeding 
10,009 florins a year, and under such circumstances the expedi- 
tion is to be confined to geographical investigations. Particulars 
could not yet be given, since the proposals of the Society were 
