461 
LEEDS CHEMISTS’ ASSOCIATION. 
A cordial vote of thanks to Mr. Mercer for his able and interesting lecture concluded 
the proceedings of the evening. 
N.B.—The Honorary Secretary desires to correct an error he unwittingly fell into in 
reporting the remarks of Dr. Edwards at the Eighth General Meeting on the 11th of 
February. The requisition referred to was not one emanating from the United Society 
of Chemists and Druggists, but from members of the Pharmaceutical Society addressed 
to the Council of that Society. 
LEEDS CHEMISTS’ ASSOCIATION. 
The Fifth Meeting of the Session was held at the School of Art, on the evening of 
January 27th, when a lecture was delivered to a large audience of Members, Associates, 
and their friends, by Mr. J. S. Blockey, upon “ Aniline Dyes ; their history, chemistry, 
and practical applications.” The lecture was copiously illustrated by specimens and 
experiments, and its author received the best thanks of the meeting. 
The Sixth Meeting was held upon the evening of February 24; the President, Mr. 
Harvey, in the chair. 
Mr. D. H. Cussons and Mr. E. Gaunt were elected Associates. 
The President alluded to the removal, by death, since the last meeting, of two old 
and respected members of the profession. 
First, their valued friend George Reinhardt, who had shown much interest in the 
Leeds Chemists’ Association, and had been from the first a member of its Committee. 
No man w r as more respected or worthy of respect for his sterling and genial qualities, 
and many would feel with himself, that they had lost a personal friend. The Committee 
had felt called upon to adopt a minute expressing their high regard for their late col¬ 
league, and their sense of the loss sustained by his relatives and friends,—which had been 
handed to the family of the deceased. 
They had also to regret the loss of Mr. Edward Smeeton, one of the oldest, if not the 
oldest chemist in Leeds, and who had for many years occupied a position in the front 
rank amongst us. He had not often attended our meetings, but had recently shown his 
interest by a liberal donation to the Library Fund. 
Mr. F. C. Clayton (Associate) read a paper upon “ Iodide of Potassium, and its Adul¬ 
terations.” After describing the various methods for the production of this salt, the 
author proceeded to describe in detail the adulterations or impurities to which it is sub¬ 
ject. About ten specimens had been examined, including those of leading makers, 
both British and foreign, as well as some that were suspected to be inferior. 
1. Iodate .—Qualitative examination by the test given in the ‘British Pharmacopoeia,’ 
showed iodate in only one sample. To determine the quantity volumetrically is diffi¬ 
cult ; hence the author had made a comparative trial by treating a known weight of 
pure iodate of potash with tartaric acid, and noting how much of the suspected sam¬ 
ple gave a similar depth of colour. He thus estimated 08 per cent, of iodate to be 
present in this sample. 
2. Chloride. —Qualitatively, traces were detected in most of the samples by AgO, N 0- 
and NH 4 0. The amount was taken by a plan given by Fresenius: 2 grammes are dissolved 
in the smallest possible quantity of water, 2cc. of N0 5 added, and then chloroform or 
benzole and more water. Agitate, when the liberated iodine dissolves in the chloroform, 
which is decanted and renewed as long as colour appears. The chlorine is left in the 
aqueous solution and is estimated by Ag0,N0 5 , either gravimetrically or volumetrically. 
No sample Lad more than one per cent, of chloride. 
Carbonate. —Tect-paper or lime-water prove its presence. Quantitatively, the author 
proposed the following ready method. A very dilute S0 3 (10 cc. = ’05 grm. K0,C0 2 ) 
is used as an alkalimetrical test upon a specimen of 1 to 4 grammes, dissolved in H 0 
with a drop of tincture of litmus. The absence of iodate must be previously proved. 
No sample exceeded one per cent, of carbonate. 
Sulphate .—The traces found in specimens of 1*5 grammes were imponderable. 
Lime and Magnesia were not found in any specimen. 
Soda .—In one case, an appreciable quantity was present. The chemical equivalent 
VOL. V. 2 I 
