Manufacturer and builder 12, 1872
As a green color may be obtained by mixing blue with yellow, some ultramarine may be mixed with the melted yellow sulphur, so as to produce a green color; therefore we advise to try this, or cobalt blue, or any other mineral color which will stand the heat of the melted sulphur. Perhaps sesquioxide of chromium, which is a very constant dark green, may do; try, also, Prussian blue. For red we should try red sulphuret of antimony, or the so-called American vermilion, which is a red chromate of lead. However, the sulphur may discolor this, as it has great affinity for lead. The best advice we can give to you is to try; that is what every chemist has to do, in order to solve new problems. Only the experienced chemist may save time, by knowing what will not satisdy the conditions, and what perhaps may.