stake not,
we mentioned a treatise of Rubens--"De Lumine et Colore"--said to have
been, somewhat more than half a century ago, in the possession of a
canon of Antwerp, a descendant of Rubens: surely it may be worth
enquiring after. It is said to be in Latin, which, not being a living
and moveable language, is the best form from which we could have a
translation upon any subject relating to the arts.

FOOTNOTES:

[Footnote 5: See TINGRY'S _Painter's and Varnisher's Guide_. 1803.]

[Footnote 6: Take two pounds two ounces and a half of borax, and one
pound of acetate of lead, dissolve each in at least a pint of hot water,
mix together the two solutions, and allow the precipitate to subside.
Pour off the supernatant liquor as soon as it is clear, add some fresh
water (rain water is preferable) to the precipitate, and agitate. Then
pour the precipitate, whilst it is distributed throughout this last
addition of water, upon a filter of white blotting paper, and when the
water has passed through the filter, add more water. These fresh
additions of water must be repeated three or four times, merely for the
purpose of washing away all traces of the liquor which was retained by
the first precipitate, and which was formed by the first admixture of
the two solutions. The precipitate, when well washed, is to be placed in
a Hessian crucible, and exposed to a red heat for half an hour. A clear
glass will be formed; which must be reduced to a very fine powder.]

[Footnote 7: "As the very peculiar property which a saturated solution
of borax possesses, of uniting so readily with oil in any proportions,
has never yet been noticed by chemical writers, I experimented with its
constituents, boracic acid and soda, separately, with a view to
determine whether the results were to be attributed to the acid, to the
alkaline base, or to the particular salt formed by their union.

"One hundred parts of borax may be said to consist of:--

Parts
Boracic Acid, 35.80
Soda, 16.85
Water, 47.35

Consequently, 24 fluid ounces of water, holding in solution 1 ounce
(avoirdupois) of borax, will contain about 4.16 per cent of borax, or
0.702 per cent of soda only.

"I first tried the effect of a saturated aqueous solution of boracic
acid with linseed oil. They would not unite. I then prepared some
caustic soda by boiling a solution of carbonate of soda with q