SCIENTIFIC SUMMARY. 
375 
sulphides in water has been proposed. It is the nitro-prusside of sodium. 
When this is added to water containing alkaline sulphides, a deep purple 
coloration is produced. 
Physiological Action of Narceine. — The researches of M. Linne, which 
have been very recently published, show that this alkaloid, while possessing 
all the useful qualities of opium, has none of its objectionable qualities, such 
as the constipating influence on the intestinal canal. The following are some 
of M. Linne’s conclusions : — (1) Narceine is unquestionably of all the alka- 
loids of opium that which has the greatest narcotic power. In the majority 
of cases morphia and codeia do not produce as sound or as prolonged sleep 
as results from the use of narceine. (2) Narceine differs from the other 
alkaloids of opium in producing little perspiration, and in causing no loss of 
appetite or nausea. (3) So far from producing constipation of the bowels, it 
causes relaxation, and in large doses actually gives rise to diarrhoea. (4) It 
not only produces sleep, but diminishes pain. (5) It has one peculiar action 
— it suppresses the flow of urine. — Yide Journal cle Chimie Medicate , May. 
The Albumen of the Blood during Cholera. — Some very valuable experi- 
ments upon the nature of the albumen of the blood in choleraic patients 
have recently been made by M. Papillon, and have been fully detailed in the 
Journal de VAnatomie (No. 2). M. Papillon, who has chemically tested the 
albumen of the blood during the progress of cholera, arrives at these five 
conclusions : — (1) This albumen, placed for four days in water, became 
neither hydrated nor swollen ; it remained just as it was when first added, 
although ordinary albumen is either dissolved or swells up under the same 
circumstances. (2) It does not dissolve in potash or soda, even at an elevated 
temperature, although ordinary albumen is soluble in these reagents, even at 
ordinary temperatures. (3) When treated with hydrochloric acid, it slowly 
di&solves, and the solution, instead of having the usual deep-violet colour, 
is only faintly tinted. (4) At the ordinary temperatures, common albumen 
decomposes rapidly a mixture of nitric and sulphuric acids, nitrous vapours 
being disengaged. Choleraic albumen does not do so at the ordinary tem- 
peratures. Ordinary albumen is very rapidly dehydrated by sulphuric acid ; 
the choleraic albumen is affected only after a long exposure. 
Perivascular Canals in the Brain and Spinal Coro. I have been demonstrated 
by Herr His, a notice of whose observations is published in the May number 
of the Archives des Sciences. These canals may be seen as grooves, which 
traverse sections of the spinal cord. They are more distinct in the grey than 
in the white substance, and each of them incloses a blood-vessel, which either 
lies freely in the cavity, or is attached to its walls. In the brain they lie 
between the nervous matter and the pia-mater. Herr His thinks they are 
connected with the lymphatic system, and that they are analogous to the 
reservoirs which in the frog lie between the muscles and skin. 
