ber of industrial effects are obtained by
suitably varying the mixtures applied.

_Cellulose-indiarubber._--The viscose, in its concentrated form, can be
incorporated with rubber-hydrocarbon mixtures, and these mixtures can be
used both as water-proofing films, as applied to textiles, or can be
solidified into the class of goods known as 'mechanicals.' The cellulose
not only cheapens the mixture, but produces new technical effects.

_Spinning._--The viscose is spun by special methods, patented by C. H.
Stearn. As produced in thread form, the diameters are approximately
those of natural silk. In commercial form it is a multiple thread (of 15
or more units) at from 50-200 deniers on the silk counts. It is a thread
of high lustre, and more nearly approaches the normal cellulose in
chemical properties than any of the other artificial silks. It can also
be spun in threads of very much larger diameter, which can be used as a
substitute for horsehair, for carbonising for incandescent electric
lamps, &c.

_Cellulose Esters._--These are conveniently made from cellulose,
regenerated from the solution as sulphocarbonate. The tetracetate is
made from this product on the industrial scale. Nitrates are
conveniently made by treatment with the ordinary mixed acids. For fuller
details the original report may be consulted.

VISKOS.

R. W. STREHLENERT (Svensk Kemisk Tidskrift, Stockholm, 1900, p. 185).

A report on the industrial development of viscose, covering essentially
the same ground as the above.

~Ueber die Viscose.~

B. M. MARGOSCHES (Reprint from Zeitschrift fuer die gesammte
Textil-Industrie, 1900-01, Nos. 14-20).[11]

~Report of Committee on the Deterioration of Paper.~

(Soc. of Arts, 1898.)

(p. 304) The Report of a Representative Committee appointed by the
Society of Arts to inquire into the question of qualities of book papers
in relation to their several applications, and more especially for
documents of permanent value.

The report first discusses the two directions of depreciation of papers
in use: (1) Actual disintegration shown by loss of resistance to
fracture by simple strain, and by loss of elasticity--i.e. increase of
brittleness; (2) discolouration. These are independent effects, but
often concurrent. They are the result of chemical changes of the
cellulose basis of the paper, brought about by acids or oxidants used in
the process of manufacture, and not completely removed from the pulp, or