38 REPORT—1868. 
usual equivalent in organic bodies. This seems to indicate a difference of consti- 
tution in these two great classes of acids. 
The well-known group of metals, iron, nickel, cobalt, and manganese give, in 
their protosalts, respectively 5-7, 5-8, 5:4, and 5:9, the same number within limits 
of probable error; but iron in its ferric salts or in the case of the compound 
cyanides gives about double that number. A similar case of “ Diphotism” occurs 
with manganese in its ordinary salts, and in the condition of permanganate where 
it was determined at 115. Chromium and aluminium belong also to this grotip, 
giving analogous numbers. 
There is no appreciable difference in the refraction of solutions of tartari¢ and 
racemic acids; the first giving 45:25, the second 45:10. 
The specific refractive energies of the metals already examined are (with one or 
two eae sae in the inverse order of their chemical equivalents. If this should 
prove to be a law, it may be the means of deciding between the multiple numbers 
that are assigned as the chemical equivalents of certain elements. 
Different Spectra of one Chromium Salt. By BR, Guxstn. 
Note on Methylacetonamine, Ethylacetonamine, and Amiylacetonamine. 
By FRepEerick GuTHRie. 
Acetonamine is obtained by digesting acetone for many days in a large flask 
containing dry ammonia, and evaporating off the excess of acetone in a water- 
bath. The composition of acetonamine is given as C, H,, N.. 
If syrupy acetonamine be mixed with iodide of methyl heat is evolved, and 
direct union ensues. A crystalline body is formed, soluble in water, and more so 
in alcohol, which is found after purification to have the formula C,H,,N, 
(CH, 1),, or iodide of methylacetonamine 
Iodide of amyl gives rise to a similar body; but the formation of the amyl 
compound requires the application of heat. The iodide of amylacetonamine, 
C,H, N, (C; H,, D,, crystallizes from alcoholic solution in pearly scales. Chloride 
of amylacetonamine may be formed in a similar manner. 
The iodide of ethylacetonamine is more difficult to obtain, but its composition 
and properties are similar to the methyl and amyl derivatives. 
Note on the Vesicular Structure of Copper. 
By Dr. Marrutessen, 7.R.S., and Dr. W. J. Russurz, F.C.S8. 
At the Meeting of the British Association at Manchester, the authors described 
some experiments on the vesicular structure of copper, and showed that it might be 
produced by the action of such reducing-agents as hydrogen, carbonic oxide, coal- 
gas, and charcoal on melted copper containing suboxide. The numerous experiments 
made abundantly proved that, with pure copper fused entirely out of contact with 
the air, no vesicular structure is produced ; but, on the other hand, if fused copper 
be exposed, even for a moment, to the air, and then charcoal be thrown upon it, or 
it be exposed to the action of a reducing-gas as it cools, then vegetation and spitting 
of the metal is always produced, and it is found to be more or less vesicular. 
This explanation of the phenomenon is apparently so complete and satisfactory, 
that the authors would not have again returned to the subject if M. Caron had 
not obtained results which lead him to conclusions somewhat different from theirs. 
He fused considerable quantities of copper, some 200 erms.,in a boat within a large 
porcelain tube, and was able to observe the changes which the copper underwent. 
On passing a current of hydrogen or carbonic oxide through the tube, the copper 
being melted, he believes that an absorption of these gases takes place, and since 
they are entirely given out again on the metal cooling, this elimination of the gas 
causes a spitting and a vesicular structure in the metal. 
_ M. Caron states further, that when the vessel which contains the melted copper 
is made of graphite, unglazed porcelain, or lime, there is no vesicular structure 
produced ; in fact, as far as his experiments go, the spitting only occurs when the 
fusion takes place in a glazed porcelain vessel. The authors have repeated M. 
