Marking:

(Embossing on one side) J. M. CO.
SOLE AGENTS

(Embossing on other side)

J. P. CO. HFD CT.
MAKERS

(Possible embossing at top of pinhole)

11

[The number at the top of the pinhole is not definitive but is partly inferred by a clear number at the top of the large truncate]

4.1 to 4.8 inches wide at the base 
[very distorted base - see picture]
(Probably 4.5 inch nominal diameter)
4.5 inches tall

The " J.M. CO." is probably Johns-Manville Co.