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17)
[[left margin]] Rec^t. for Lacque. [[/margin]]
[[right margin]] Of the Sun standing still, & the shadow On Ahaz's Dial going backward.  See much better in Parkhurst's Heb. Lex under ץדת p. 475. the 2^d Edit. [[/margin]]

To make a very good lacque, or varnish.
Take a very clear lye of pot-ash, or tartar, add to it a very small quantity of a solution of a [[strikethrough]] l [[/strikethrough]] lum; put the lye into a very large glass vessel; take some powdered cochineal, which must be carefully sewed into a linen bag, which stir about in the lye till no colour remains in it.  That which is first extracted is best, and may be kept in a separate glass.  When the colour is all extracted, take some very clean [[strikethrough]] allum [[/strikethrough]] alum-water, which pour on the lye, till the whole is curdled; it must then be filtered, and the varnish purified.
General Mag. March. p.134 (A.D. 1764)
[[right margin]] Two Cases [[/margin]]
The German powder for silvering small plaster busts, statues, or carved work, called Argentum Mosaicum. 
[[left margin]] Argentum Mosaicum. [[/margin]]
One pound of very pure [[strikethrough]] tim [[/strikethrough]] tin, melted in a crucible:  when it begins to run into fusion, add 
[[right margin]] Objection [[/margin]]
to it an equal quantity of bismuth or tin-glass and stir the mixture with an iron rod, or stem of a tobacco-pipe, till the whole be entirely melted and [[strikethrough]] incop [[/strikethrough]] incorporated.  Take the crucible then from the fire; and, after the composition has cooled a little, but while in a fluid state, pour into it a pound of quicksilver, gradually; stirring it in the mean time, that the mercury may be throughly conjoined with the other ingredients. 
[[right margin]] Measure of Fig^s for Dials, & [[strikethrough]] the [[/strikethrough]] a computation of the Guilding upon one. [[/margin]]
When the whole is thus commixed, pour out the mass on a flat marble stone; where, as it cools it will take the form of an amalgama or metalline paste, which will be easily bruised into flaky powder, and is then fit for use.
[[left margin]] How used. [[/margin]]
This powder may be either tempered with gum water; or rubbed over a ground properly sized with some white substance, as flake-white, or white-lead for oil; Whiting is used, or where the glover's or parchment size is used.  Tobacco-pipe clay, with a very little lamp-black to give it a silvery greyishness, is still better:  and it will take a very elegant polish from a dogs tooth or a burnisher's and holds its colour much better with a slight coat of varnish over it, than any true silver powder.  a D^o.
[[left margin]] Counterfeit Amber. [[/margin]]
A Composition in Imitation of AMBER.
Take the yolks of sixteen Eggs, beat them well together in an earthen Pan well glazed, then take two ounces of Gum Arabic, and one ounce of the Gum of Cherry-trees, reduce them into powder, and mix them with the Yolks, that so they may dissolve, and be incorporated by stirring them frequently about; this done, set them for six or eight days in the sun, and they will by Degrees grow harder and harder.
[[right margin]] Scripture places which assert the Earth's stability & the Sun's Motion [[/margin]]
You may, before they are thorough dry, form or impress what you will in some mould, and lay them again in the Sun, or some warm place to dry, & whatsoever you have made, will look clear of the colour of Amber, and have its natural Qualities to draw up straw or paper.