TRANSACTIONS OF SECTION B, 501 
5, Hexachlor-a-Picoline and its Derivatives. 
By W. J. Seti, IA., F.R.S, 
With the object of assisting in the orientation of some of the lower chloro and 
other derivatives of pyridine it was thought advisable to study the action of 
chlorine on the hydrochlorides of various methylpyridines. The substance 
employed to begin with was a-picoline after purification of its double salt with 
mercuric chloride. 
The chief solid product of the chlorination of a-picoline is a white crystalline 
substance having the formula C,HC1,N, and which readily gives trichlorpicolinie 
acid on heating with 80 per cent. sulphuric acid; it therefore contains the fully 
chlorinated methyl group CCl,, which, as usual, breaks down to COOH with 
elimination of HCI. 
Trichlorpicolinic acid when distilled with glycerine is readily resolved into a 
trichlorpyridine (m.p. 72-8°), first obtained by Keiser, and described by him as the 
hydrochlorate of a dichloropyridine, but since shown by Sell and Dootson to be 
a trichlorpyridine. The positions of the chlorine atoms in this compound are 
unknown, but various considerations lead to the supposition that they occupy the 
positions 3, 4, 5. i 
To prove that this is so, recourse was had to the synthesis from the trichlor- 
picolinic acid of a compound whose constitution is established. Such a substance 
is 2-amino-3, 4, 5-chlorpyridine. The trichlorpicolinic acid was converted into 
the amide, and this into the amino derivative by the Hofmann reaction, On 
comparison the aminotrichlorpyridine was found to be identical with the 
2-amino-3, 4, 5-trichlorpyridine obtained from other sources, 
6. The Change of Conductivity in Solutions during Chemical Reactions. 
By P. V. Bevan, JA. 
The experiments described in this paper were made to determine, if possible, 
the part played by the hydrogen ions of the acid used in the inversion of cane 
sugar. The object was to attack the problem of catalytic action by applying the 
Kohlrausch method of determining the conductivity of the solution. It seemed 
certain that, the action being conditioned by the presence of the hydrogen ions, 
their capacity as carriers of the current must be affected, and so it was thought 
that some light might be thrown on the actual mechanism of the action. If the 
resistance of a solution of cane sugar with a small percentage of hydrochloric 
acid be obtained at various stages of the inversion, a change of resistance, which 
may amount to 10 or more per cent. of the initial resistance, occurs during the 
inversion. Two factors which contribute to this change are the loss of water 
during the inversion and the change of the ionic viscosity of the solution conse- 
quent on the transition from the cane to the inverted sugar. The results so far 
obtained have not enabled me to discriminate between the various causes pro- 
ducing the total effect. Another series of experiments was made determining the 
conductivity of solutions containing a constant quantity of sugar per volume but 
a varying amount of acid. On plotting the concentration (HCl) and_ specific 
molecular conductivity one obtains a curve, which at concentrations down to 
about ‘005 normal is a straight line parallel to the concentration axis, but for 
concentrations lower than this the curve drops towards the concentration axis ; 
the specific molecular conductivity decreasing at a concentration of ‘0002 norma), 
there are indications that the curve becomes again parallel to the axis of concen- 
tration, At this small concentration, however, the observations so far made are not 
very consistent, and at present stress is not laid on this point. The experiments 
show in this way an effect on the molecular conductivity, which can be explained 
by supposing the H-ions are loaded up, forming the centre of a group consisting 
of one or more sugar molecules and one or more water molecules. This kind of 
group need not be considered as a stable compound, but may be merely in a 
state where it can split easily into water and cane sugar again, or in some cases 
