ASBESTOS AND Il^S APPLICATIONS. 439 
demands careful attention on the part of the engineer in charge. If carefully 
manufactured and properly used, asbestos is the best material for packing the 
glands of steam-engines ; but if ignorantly made up and carelessly used, it is 
probably the worst. 
A great deal of yarn is woven into cloth, and is adapted for a great variety 
of purposes. One noteworthy application is for fire-proof curtains, and several 
of these have been supplied by Mr. Bell for theatres in Great Britain, the United 
States, and elsewhere. So important is this material considered in regard to the 
prevention of the spread of conflagrations that a company has been formed in 
New York with the sole object of extending its use in the shape of protective 
shields, either permanently fixed or applied in case of a sudden emergency. In 
relation to this apphcation, a fire-shield was recently exhibited at a meeting of 
the Firemen's Convention held at Rochester, N. Y., and attracted very great 
attention. The shield consisted of a piece of pure asbestos cloth about twenty 
feet square, and supported on an iron frame. A pile of pine wood saturated with 
petroleum and tar was built on the windward side of the curtain, and set on fire. 
The blaze was tremendous, and the heat so intense that persons could not stand 
within fifty feet of the burning mass on the exposed side. On the side protected 
by the shield, however, the heat was scarcely felt, and a dummy erection of wood 
and glass, which was placed close beside it, was not in any way injured. The 
curtain, of course, did not suffer, and was as good after the experiment as it was 
before. 
For forming the joints of pipes exposed to the action of moisture, and for 
man and mud-hole doors requiring frequent removal, asbestos woven cloth is 
very largely in demand. In these cases, asbestos millboard, which is the cheap- 
est form of jointing material, is comparatively worthless, if, indeed, it is not 
absolutely objectionable, from its permeability to water, which soaks through 
and attacks the iron of the bolts, and it was therefore necessary to devise a com- 
bination which would eff'ectually resist the heat and damp. This is provided in 
what is known as asbestos and India rubber woven sheeting, which is made in 
any thickness, and is supplied either in sheets to cut to the required shape, or in 
a tape from one to two inches wide, which can be cut to lengths and bent to 
circle or oval without puckering. When all other materials have failed to give 
satisfaction, this has answered admirably, and in the case of man-hole and mud- 
hole doors and feed-water pipes, the joint can be broken twenty times without 
requiring renewal of the strip. 
The last application of the yarn which we shall mention is the manufacture 
of rope and cord. Having great tensile strength, and being unaffected by heat 
and damp, this material is in course of introduction for sash-lines and for ropes 
of fire-escapes. It is also adopted for covering rollers in print-works, especially 
when aniline dyes are used, and in cases when it is exposed to great heat and to 
the action of hydrochloric acid. Asbestos cord has also been found to be the 
most effectual material for making the joints of the hot-air pipes for blast-furnaces, 
which are exposed to an exceedingly high temperature. The jointing consists of 
