Asbestos, the well-known fireproof and acidproof fibrous mineral, is the basis of several substances useful to the builder.1

The raw material comes from Italy, Canada, California, Australia, etc. The two first are the best in the order given. Italian asbestos is grey or brown in colour, Canadian white, Asbestos Paints (see p. 428).

Asbestos Concrete Coating is of a drab colour, and is used to cover beams to retard the action of fire upon them; 100 lbs. will cover 200 square feet 1/16 inch thick.

Asbestos Roofing is made from canvas cemented to a surface layer of felt and a Manilla lining in compact flexible sheets resembling leather.

It is supplied in rolls about 381/2 inches wide, containing 200 square feet, and weighs about 85 lbs. per square.

Asbestos Sheathing is fireproof, and used for lining wooden partitions, ceilings, etc. It is made in rolls of from 60 to 100 lbs. 42 inches wide, weighing about 6 lbs. per square; also "double thick," weighing about 10 lbs. per square.

Asbestos Building Felt is fireproof; it is made in rolls of about 70 lbs. weight, 36 inches wide, weighing about 60 lbs. per square; also "extra heavy," weighing about 16 lbs. per square.