748 REPORT—1896. 
5. On the Amides of the Alkali Metals and some of their Derivatives 
By A, W. Trruertey, Jf.Sc., Ph.D. 
Ammonia, by the substitution of one atom of hydrogen by the alkali metals, 
gives rise to a series of amides of interesting properties. The following were 
prepared: sodamide, NaNH,; potassamide, KNH, ; lithamide, LiNH,; and rubid- 
amide, RbNH,. The metals, on heating in ammonia, rapidly decompose it, form- 
ing the respective amides, especially lithium, whose action is very energetic. 
The amides are white crystalline substances, easily decomposed by water. On 
heating they distil or sublime without decomposition, except at high temperatures, 
when they split partially into their elements. No nitrides result, although these 
were stated by Davy to be formed by heating the impure sodamide and potass- 
amide he obtained—his results having been vitiated by the glass vessels employed. 
The melting-points of the amides are very different, and bear no connection 
apparently with the atomic weights of the metals. Several substitution deri- 
vatives were exhibited, obtained by replacing the H atom of the NH, group by 
alkyl and other groups. : 
6. Interim Report on the Bibliography of Spectroscopy. 
See Reports, p. 243. 
7. Report on the Action of Light on Dyed Colowrs.—See Reports, p. 347. 
FRIDAY, SEPTEMBER 18. 
The following Reports and Papers were read :— 
1. Report on the Carbohydrates of Barley Straw.—See Reports, p. 262. 
2. The Retardation of Chemical Reaction from Diminution of Space. 
Sy Professor Oscar LIEBREICH. 
This subject may be regarded from the point of view either of Chemistry or of 
Physics, as it occupies a position on the borderland between those sciences. 
We know that some of the phenomena of motion in capillary tubes differ from 
those in larger vessels filled with liquid. The melting-point is higher, the freezing- 
point is lower, the boiling-point is retarded. Of the phenomena of motion which 
go by the name of chemical reaction we know as yet nothing, for the condensa- 
tion of gases in finely pulverised substances also belongs to purely physical 
phenomena. 
This investigation arose out of a previous examination of chloral hydrate, 
the decomposition of which into chloroform takes place according to a well-known 
formula. 
Under certain conditions this. substance undergoes a molecular change. If the 
melted crystals—in appearance a matted mass of needles—are placed in benzene, 
isolated glassy-hard needles are obtained. The most varied experiments, made 
for the purpose of discovering whether a different chemical substance had been 
formed, proved unavailing ; but there wascertainly a change as far as physical quali- 
ties were concerned. The matted needle-mass dissolved in water without increase 
of volume; while in the case of the isolated needles an increase of volume was 
proved. No chemical difference being observed, the author endeavoured to find 
out whether both substances were alike in the velocity of reaction. 
When soda solutions are mixed with solutions of chloral hydrate, the chloro- 
form dogs not separate out in oily drops, but forms a nebula of chloroform in the 
