| As a means of simplifying this rather complicated technique and obviating the necessity of grinding the colors in the black oil, an analogous medium has been worked out for the use of students with which tube colors can be used. In this, the litharge (instead of being deposited and largely eliminated from the medium, as it is with the black oil) is incorporated into the paste, thereby making it much stronger and capable of overcoming the dilution by the raw oil with which the tube colors are ground. It is made in the following way (all measurements are given by weight):. Litharge. ................... . . . . I part Beeswax............. .......... . . . I part It is advisable to grind the litharge with a little of the oil before mixing it with the rest of the oil. The mixture is then simply heated to 250 degrees centigrade and when it turns black the product is finished. In cooling it thickens into a paste.. In actual usage, the results are very close to the true Italian medium. This paste has the advantage that it can be made by anybody, without difficulty. It is mixed (by means of the palette knife) into each of the colors on the palette, including the white. There can be no definite prescription for its use, as it is a matter of individual taste; also the use may vary with different subjects. It can be thinned with raw oil or, preferably, with essence of turpentine. This can be worked into it with the palette knife for use on the palette, or else kept in the oil cup for further dilution of the colors. |