SCIENTIFIC SUMMARY. 
209 
the two eminent chemists above named. It resulted from the fact that an 
analysis of Dr. Redwood, which gave forty grains of alum in a four-pound 
loaf was disputed by the bakers, who asserted that they put no alum into 
the bread, and demanded an independent analysis, which was made by 
Mr. Wanklyn, with the result quite different from that of Professor Red- 
wood, viz., that there was no alum in 1,500 grains of the bread. The 
magistrates before whom this case came dismissed it. There is thus a very 
important point to be discussed, viz., whether Professor Wanklyn or Professor 
Redwood is correct. We give no decided opinion on the point, but we cer- 
tainly incline to the belief that Professor Wanklyn is by no means in the 
wrong. 
'Where is Thallium Found ? — Mr. W. Crookes, F.R.S., has published in 
several numbers of the ‘‘Chemical News” a most valuable paper on the 
estimation of thallium, in which he gives an exhaustive list of the localities 
in which it is found. Thallium is, he says, a very widely distributed 
constituent of iron and copper pyrites. Upon examining a large collection 
of pyrites from different parts of the world, it was found present in more 
than one-eighth. It is not confined to any particular locality. Amongst 
those ores in which it occurs most abundantly (although in these cases it 
does not constitute more than from the 100,000th to the 4,000th of the bulk 
of the ore), may be mentioned iron pyrites from Theux, near Spa in Bel- 
gium, from Namur, Philipville, Alais, the south of Spain, France, Ireland, 
Cornwall, Cumberland, and different parts of North and South America ; 
in copper pyrites from Spain, as well as in crude sulphur prepared from this 
ore ; in blende and calamine from Theux ; in blende, calamine, metallic 
zinc, sulphide of cadmium, metallic cadmium, and cake sulphur from Nou- 
velle-Montagne j in native sulphur from Lipari and Spain; in bismuth, 
mercury, and antimony ores, as well as in the manufactured products from 
these minerals (frequently in so-called pure medicinal preparations of these 
metals) ; in commercial selenium and tellurium (probably as selenide and 
telluride) ; and various other substances. Vide “ Chemical News,” Feb. 13, 
1874. 
A Phosphide of Antimony. — In a late number of the u Proceedings ” of 
the Chemical Society of Berlin, Mr. W. Ramsay, in a preliminary notice on 
this subject, states that Mr. R. W. E. Macivor, of the Andersonian Uni- 
versity, Glasgow, has succeeded in forming phosphide of antimony, PSb, as 
a red powder, insoluble in benzol, ether, and bisulphide of carbon, and con- 
taining — 
Antimony . . . .79-48 
Phosphorus .... 20-21 
99-69 
See also u Chemical News,” February. 
Reduction of Carbonic Acid to Carbonic Oxide by Phosphate of Iron . — 
Mr. S. H. Horsford has found that when carbonic acid and a mixture of 
phosphate of soda and green vitriol with a little water are introduced into 
a tube, the carbonic acid is gradually reduced to carbonic oxide. The author 
considers this phenomenon as very important for vegetation. Vide u Bull, 
de la Soc. Chim. de Paris,” Yol. xx. No. 10. 
What are the Adulterations of Tea? — This subject, which all — whether 
VOL. XIII. — NO. LI. P 
