The Journal of the Board of Arts and Manufactures for Upper Canada, July 1867
M. Ch. Guerin called the attention of the French Academy to a new method of obtaining, by a cold process, a silicate completely insoluble which can be applied either as an external coating, as in the case of glass or iron, or made to penetrate through the interior of the substance, as for the preservation of wood and other vegetable matters. The process is very simple: a thin coating of slaked lime made into a paste with water, or whitewash, is laid on the object to be silicatized, and when this has been allowed to dry, silicate of potash is applied over the coating; the effect, it is asserted, being that all the portions touched by the solution of potash become completely insoluble, and of very great adherence. In order to obtain an insoluble silicate in the interior of a substance, all that is necessary is to impregnate it by immersing it in whitewash, or lime water, and when it is dry to steep it in a solution of the silicate of potash.
By this means it is proposed to prevent the decomposition of vegetable substances by petrifying them; also to protect porous building stones and bricks against air and damp; iron, by a coating of paper, pulp or other finely-divided woody matter, mixed with slaked lime.
Again, letters, characters, or any other device can be traced with the silicate on any surface spread with lime, and those portions touched by the silicate will alone adhere and become insoluble. Or, if they be traced with a solution of gum arabic, and the whole be washed over with the silicate, the parts protected by the gum can be washed off, the rest remaining in relief, as the letters etc., do in the first place.
The process sems to be substantially the same as the English process, known as Ransome’s.
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