One of our exchanges mentions an experiment which was made
twenty-seven years ago, of dipping shingles into hot linseed oil prior
to nailing them on the roof: and although they have not been painted,
they are said to continue perfectly sound as when first put on. They
were of the common pine, and as much exposed as roofs in general. This
instance may be sufficient to establish the fact that shingles thus
prepared, will last longer without painting than they could possibly
be preserved by painting in the usual way. As a security against fire,
however, we should recommend that they be first dipped in a hot
solution of common salt; and afterward, when dry, be dipped in the hot
oil. The expense will be trifling, and there can be no doubt of their
durability, and there will be no danger of their taking fire from
sparks or cinders.
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