"Hard coal" Quotes from Famous Books
 ... heat is to be used, it is much safer to use some non-inflammable material such as asbestos or mineral wool. A cheap substitute and one which is easily obtained are the small cinders sifted from coal ashes, preferably those from soft coal. However, the cinders from hard coal burned in the kitchen range will do. If a fire-proof packing material is not used, a heavy pad of asbestos should be placed at the bottom of the metal lining, and a sheet or two of this paper should be placed between the lining ...
— Ontario Teachers' Manuals: Household Science in Rural Schools • Ministry of Education Ontario |
