65 
Kelhofer, W., discusses the estimation of invert sugar by weighing 
the dried precipitate obtained by means of Fehling’s solution. — 
Ztschr. f. anal. Chem. Wiesb., 1906, v. 45, pp. 88-91, 745-747. 
Tamisier, D. C., points out an error in the estimation of sugar by 
means of Fehling’s solution caused by the solution of the oxide of 
copper in the solution. — Bull. Pharm. du Sud-Est., Montpel., 1906, 
v. 11, pp. 202, 203. 
nessler's reagent. 
Buisson, A., asserts that the quantitative estimation of ammonia in 
water by Nessler’s reagent is unreliable. (C. R., 1906, v. 143, p. 
289.) — Biochem. CentrJhl., Leipz., 1906-7, v. 5, p. 814. 
Rosenthaler discusses the behavior of Nessler’s reagent with several 
glucosides, particularly saponins. — Pharm. Zentralh., 1906, v. 47, 
p. 581. 
THALLEIOQUIN REACTION. 
Fiihrer, Hermann, presents a study on the nature, history, and 
chemistry of the thalleioquin reaction. — Arch. d. Pharm., Berl., 1906, 
v. 244, pp. 602-622. 
ARSENTJM TESTS. 
Coblentz, Virgil, discusses the objections to the old and the method 
and philosophy of the new test. — Apothecary, Boston, 1906, v. 18, 
p. 31. 
Hill and Collins (Chem. and Drug., Sept. 30, 1905, 548) discuss the 
application of Gutzeit’s test, and suggest the use of apparatus some- 
what different from that ordinarily used. — Proc. Am. Pharm. Ass., 
1906, v. 54, pp. 848, 849. 
Goods and Perkins conclude, as to the reliability of the Gutzeit 
test, that it is not possible to prepare permanent standards; there- 
fore, all determinations must be done in parallel. * * * With 
reference to the different methods of detecting arsenic, the Marsh- 
Berzelius apparatus requires a lot of experience, but in the hands 
of an experienced manipulator may be said to be practically infalli- 
ble. The same remarks apply to the electrolytic method when a lead 
cathode is used, although this is not quite so delicate as the Marsh- 
Berzelius apparatus. The Gutzeit test requires care and experience 
and then leaves little to be desired. In all the methods the samples 
to be tested should be as free as possible from foreign substances, 
especially metallic impurities. For general testing purposes they 
think the Gutzeit test has decided advantages over the Marsh- 
Berzelius; but for cases of poisoning, of course, the Marsh-Berzelius 
apparatus is the one which should be employed. A lengthy discussion 
follows. — J. Soc. Chem. Ind., Bond., 1906, v. 25, pp. 507-512. 
11667— Bull. 58—09 5 
