February 18,1871.] 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
G63 
his lint, the printer his paper, the navy its ropes, 
and the housewife her linen; and, after serving 
every useful purpose, and passing into the rag-bag, 
these invaluable fibres go— 
“ Into the paper-mill, and from its jaws 
Stainless and smooth emerge. Happy shall bo 
Its renovation, if on its fair page 
Wisdom and Truth their hallow’d lineaments 
Trace for posterity. So shall its end 
Be better than its birth.” 
Indeed, so indispensable has the success of the flax 
crop been considered, that its failure has been fre¬ 
quently described as a national calamity, and is 
mentioned by Moses as one of the Egyptian punish¬ 
ments. 
Hardly an author can be mentioned who does not 
in some way or other speak of this lowly plant. 
Virgil describes the flax crops, with the other pro¬ 
fitable speculations of the husbandman:— 
“ Urit enim lini campum seges, urit avenoe.’ 
Horace tells of the benefit derived from straining his 
Massican wine through the linen filter:— 
“ ut ilia 
Integrum perdunt lino vitiata saporem.” 
The products of this humble plant, familiar as 
they are to every apprentice, most commonly are 
allowed to pass by without the slightest thought 
about their hidden interest. To the student the tow, 
the linseed oil, the linseed and the linseed meal are 
among the wonders of nature. 
Specimens of the Linuin usitcitissimum may be 
collected at Henbury, Keynsham, Ashton, and seve¬ 
ral other places in the neighbourhood of Bristol. 
The microscopic structure of the seeds and stem 
of the flax plant must not be passed over, because its 
knowledge is very necessary to the analyst, who is 
often called upon to defeat the schemes of the adul¬ 
terator of oil cake, linseed meal, or various fabrics. 
When the stem of the flax plant is soaked in 
water the fibres of the inner bark, or liber, may be 
separated for examination. From these is produced 
our tow. When a few fibres are examined by the 
microscope they are seen to consist of long cells of 
ceflulin from to Woo inc]l in diameter. These 
may be used for experimental observations on the 
chemical properties of cellulin (CjgH^Oj.). When 
tow is boiled with diluted sulphuric acid, it is parti¬ 
ally converted into dextrine and grape sugar:— 
c 19 h 3 „ 0 13 + H 2 O = 2(C 6 H 10 O s ) + c s h 12 o, 
Cellulin. Dextrin. Grape Sugar. 
When acted upon by nitric acid or alkalies, oxalic 
acid is formed:— 
C ls H s0 O ls + 0 27 = 9 (C 2 H 2 0,) + 0H 2 O. 
Cellulin. Oxalic Acid. 
When strong nitric and sulphuric acids are mixed 
with flax fibres, pyroxylin is produced, as in the 
B.P.:— 
C 13 H 30 0 15 + G HN 0 3 = C 13 H 24 , ON 0 2 , 0 15 + 6 H 2 0. 
Cellulin, Nitric Acid. Pyroxylin. 
The tow that is most generally used is not derived 
from flax, but hemp, a member of the nettle family. 
It differs materially in its properties. When ex¬ 
amined under a high power the fibres, from to 
inch in diameter, are seen to be formed of 
bundles of cells, pointed at each end, closely fitted 
to each other and cemented together by a peculiar 
resin. Till prepared by boiling with strong nitro- 
hydrochloric acid the fibres are opaque, but when 
cleansed are very beautiful objects for polarized 
light. Hemp cells show traces of transverse striae, 
while those of true flax are longitudinal. Flax is 
not coloured by nitric acid, while hemp is reddened. 
When the tow derived from hemp is placed in a solu¬ 
tion of chlorinated lime it turns yellow ; when well 
washed with water and immersed in sodic sulphite, 
the yellow tint is changed into a very beautiful crim¬ 
son. This is not the case with flax, but is due to 
the presence of the hemp resin. 
When a section of the flax seed (linseed) is placed 
under the [microscope four distinct coats may be 
seen. 
The external layer is composed of hexagonal cells, 
measuring about hicli. These give the polish 
and colour to the seeds, and are filled with mucila ge; 
when acted upon by ’warm water these cells swell 
and burst. The mucilage is slightly acid, and turns 
a ray of polarized light to the left; when acted upon 
by iodine with sulphuric acid, or zincic chloride, it 
is not coloured, like the mucilage from many other 
plants. It consists chiefly of Arabic acid (C 12 H 22 Oiih 
which is soluble in water, and bassorin (Ci 2 H 20 O 10 ), 
which is insoluble unless when mixed with an al¬ 
kali. 
The next coat is a layer of rounded cells about 
inch in diameter and filled with granular con¬ 
tents. The third layer is built up with long, narrow 
cells, about -gfuo hicli in diameter, crossing each 
other at right angles, as if for the purpose of making 
a tough envelope for the seed. 
The fourth and internal layer is composed of irre¬ 
gular cells, smaller than the others, and filled with a 
kind of resin, which readily escapes from the cells 
when cut. 
The seed itself consists of very small cells, averag¬ 
ing inch, and filled with oil and starch. 
The seeds yield about one-fifth their weight of oil, 
having a sp. gr. ’9395. Pure linseed oil dissolves 
in five times its weight of alcohol when boiling and 
forty when cold. It solidifies at —17° 0., takes fire 
with fuming nitric acid, and when heated for some 
time at a high temperature, becomes converted into 
a dark sticky mass, which is so viscid that it may 
be used as birdlime. 
Linseed oil is a typical example of what is called 
a drying oil. By exposure to the atmosphere it 
suffers oxidation and becomes resinified. Linseed 
oil probably owes this property to the presence of 
linolein. When saponified the linolein becomes 
converted into linoleic acid (C IG H 23 0 2 ). When 
boiled with lead or manganese a margarate and 
linoleate of the metal are formed, and the drying 
quality increased. The residue, after the removal 
of the oil by pressure, is sold as oil cake, and when 
ground, as linseed meal. Both these are terribly 
adulterated with sand, clay, twigs, sawdust and re¬ 
fuse from other seeds, and which can only be de¬ 
tected and exposed by the assistance of a micro¬ 
scope. 
(To be continued.) 
Cowhage, — Mr. J. Weichselbaum, of Savannah, in a 
communication to the American Journal of Pharmacy , 
says that the irritation of the skin caused by contact 
with the leguminous pods of Mucuna pruriens (Cownage), 
may he instantaneously removed by the application of 
camphor liniment. 
