The Locomotive - Lighthouse Survival Blog

1893.] THE LOCOMOTIVE. 63
Must the Silk Worm Go?
A report has hecn received at the State Dei)artineiit from Consul Loomis, of St.
Ktioiine, jj^iving some interesting details and information in regard to tlie Cliardonnet
jtrocess of converting wood pulp into silk. This report will soon bflwpublished and dis-
tributed as a general answer to numerous iiujuiries about the process. Of course the
great ipiestion has been as to whether the new discovery could be made practicably use-
ful and valuable.
Consul Loomis tliiidvs that this question has been answered in tlie affirmative by M.
De Chanhjnnet, who has built a mill at Besancon, where the "silk " is now being manu-
factured. The raw material is made from wood pulp, which is carefully dried in an
oven and plunged in a mixture of sulphuric and nitric acids, then washed several times
in water and dried by alcohol. The ])roduct thus prepared is dissolved in ether and
l)ure alcohol, and the result is collodion, similar to that used in photography. This col-
lodion, which is sticky and viscous, is enclosed in a solid receptacle, furnished with a
filter in the lower end.
Au air pump sends compressed air into the receptacle, and by its pressure the coUo
-dion is passed through the filter, which removes all impurities and flows into a tube
placed horizontally. This tube is armed with iJOO cocks, of which the spouts are made
of glass and ))ierced by a small hole of the diameter of the thread of a cocoon as it is
spun by the silk worm. The spinner opens the cock, and the collodion issues in a thread
of extreme (h:;licacy (it takes six to make a thread of the necessary consistence for weaving).
This thread is not, however, fit to be rolled on the spools, by reason of its viscosity
and softness ;
the matter is as yet collodion and not silk.
To prochice the necessary hanbiess, the inventor resorted to a very inorenious but
simple method. The little glass tul)e already mentioned is surrounded by a small reservoir
of the same material constantly filled with water. When the thread issues from the
aperture in the manner described, it traverses this water, which takes up the ether and
alcohol, and then the collodion becomes solidified; that is to say. it is transformed into
an elastic thread as resisting and brilliant as ordinary silk. On account of the materials
employed the stuff manufactured was found to be dangerously inflanimal)le — its original
combustil)ility Ijeing at the alarming rate of two centimetres [four-fifths of an inch] a
second. Mr. Loomis says that M. De Chardonnet has apparently removed this difficulty
"by ))lunging the spun thread into a solution of ammonia, thus rendering it as slow of
conibusti(jn as any otlier material."
The consul adds: " This discovery seems to have a great future. I have talked
with a great many silk merchants, brokers, dyers, and men who manufacture silk goods,
about the Chardonnet method of ])roducing raw silk from wood, and it is universally admitted
that the process will eventually yield large, practicable, and profitable results. A
great step has been made toward this end in reducing the inflammability of the Chardonnet
silk. Another practical difficulty to be remedied in the invention is the frequent
snapping of the slender threads issuing from the cylinder by reason of unequal pressure.
This makes it impossible to maintain a standard quality for the outjnit, and consequently
there may be produced five pounds of excellent silk followed by five pounds of a comparatively
worthless quality. This difficulty is being overcome, I am told, but until it
is completely removed men of large means will not invest largely in the stock of the