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Magnesia
After numerous comparative experiments with Alumine, Silex and Magnesia, I have come to the conclusion that Carbonate of Magnesia is probably of the best material with which to dilute + modify pigments of a harsh nature which require it. It lessens their opacity, makes them stand up on the Palette, it causes them to dry with a lustre. Vermillion ground with it may be kept in tubes or bladders as other Colors, it may be put with other tints under Water. Vandycke Red and Violet de mars cannot well be used without it, (or Alumine). My method of employing it is this- Grind the Magnesia with Oil to the consistence of a pigment- take a portion of this & add an equal bulk of the pigment to be combined with it- it will seem to thick & dry, but a little grinding with the Muller will bring it to the proper texture for painting. This is a singular property of the Magnesia that being ground with a pigment already ground renders it more fluid; which is the reason why the Magnesia must be ground first & then thickened with the pigment in powder. It renders opaque Colors semi-transparent when desired.

Comparison of Diluents.

Acetate of Lead, Carbonate of Magnesia, Carbonate of Zinc, Calcined Sulphate of Zinc, and Alumine, were severally ground with Poppy oil, and nearly resembled each other, differing only as follows- The Acetate of lead had a creamy whiteness, the [[strikethrough]] Carbonate of Zinc [[/strikethrough]] Carbonate of Magnesia, light & pearly; the Carbonate of Zinc, a bone-like hue; the Calcined Sulphate of Zinc, a little lighter; and the Alumine, a wax-like appearance- the Magnesia being the clearest & most brilliant, and the Alumine the most transparent. 

On a former occasion I found that Alumine & Carbonate of Zinc, ground with Poppy Oil, had not dried for ten days in the shade; but in the sun had dried in two days- both nearly in an equal degree. 

On examining the specimens, I found that the Acetate of Lead, after a few days exposure to the air of my Painting Room in November, 
was 

Transcription Notes:
*stand up is underlined *consistence is underlined *portion is underlined *equal bulk is underlined