126 REPORT—1857. 
On Flax. By Joun P. Hopness, M.D., F.C.S., Professor of Agri- 
culture, Queen’s College, Belfast, and Chemist to the Chemico-Agri- 
cultural Society of Ulster. 
Composition of the Unsteeped Flax Stem and of the Dressed Fibre. 
For the purpose of studying the nature of the proximate compounds which 
are contained in the cells of the flax-plant, and which are in part removed in 
the steeping process, several analyses, both of unsteeped and of dressed flax, 
i.e. of the fibre in the condition in which it is brought into the market, 
deprived of the portions unsuitable for spinning, have been made by the 
Reporter. By operating upon large quantities of material, he was enabled to 
separate considerable quantities of some of the most important constituents 
of the plant, and had hoped to be ready to communicate the results of the 
investigations in which, at various periods during the past three or four 
years, he has been engaged; but, from the interruption of pressing profes- 
sional duties, he has been obliged to remain content with merely a partial 
survey of the subject. As, however, the chief labour of the investigation 
has been removed, he expects that, in the course of next year, he may con- 
clude the inquiry. In the mean time, a summary of some of the results ob- 
tained will be found interesting, and in some degree useful, as a contribu- 
tion to the chemical history of a material of so great importance to the staple 
industry of Ireland. For the proximate analyses of the plant, various methods 
of investigation were tried; but that which was preferred, as affording the 
most reliable results, was conducted as follows:—The flax, cut into small 
pieces, was in the first place repeatedly treated with cold water, so long as 
anything was dissolved. The solution was strained through linen, and after- 
wards filtered and heated to ebullition. The coagulum which was produced 
on boiling the liquid was separated by the filter, and a few drops of acetic 
acid added, which produced a precipitate of caseine, which, after twelve 
hours’ subsidence, was collected, washed, dried, and weighed. In the liquid 
from which the caseine was separated, when evaporated to an almost syrupy 
consistence, alcohol, when added, produced a bulky gelatinous precipitate of 
a greyish colour, which was collected on a filter, washed with alcohol, and 
dried. The alcoholic liquids, on concentration, afforded rich orange-coloured 
solutions, and afforded, on evaporation, reddish-brown extracts, which, in the 
case of the dressed flax, were found to contain a considerable amount of 
grape-sugar. The several precipitates and residues, after being weighed, 
were carefully incinerated, and the weight of ash obtained in each case de- 
ducted. The amount of nitrogen contained in the samples was determined 
by the method of Varrentrapp and Will, and in each case two estimations were 
made—first, of the total amount of nitrogen contained in the specimen dried 
at 212°; and secondly, of the amount of nitrogen which was retained, in the 
form of insoluble azotized compounds, in the specimen from which all soluble 
matters had been removed by treatment with water as described. The 
amount of fatty matter and oil present was obtained by treating the specimen 
dried at 212° in a simple, but exceedingly effective, extraction apparatus, 
which for upwards of ten years has been in use in the laboratory of the Re- 
porter, and has been found of great service in facilitating the treatment of 
substances with alcohol and ether. It is formed by attaching a thin glass 
flask, capable of containing about 6 oz. of liquid, by means of a small 
glass tube and sound corks, to a glass vessel of about 12 oz. capacity pro- 
vided with two openings, one being at the top and the other at the side, as 
close as possible to the bottom of the vessel. To the opening at the top of 
the vessel, a glass tube bent at right angles is affixed by means of a cork, 
