Another perplexity is in regard to the Burnt Madder. If the madders are in themselves sound colours, as I have always understood them to be, how do they lose their permanence by burning? I should like to use the Gialetto, and I rather gather from what you say that I may do so. I hear with interest what you tell me of your new varnish. As for myself, I have got to dislike the use of any resins in my work to such an extent that I have completely set them aside. Of course when a picture is finished it requires some gum, not only to protect it, but to bring up the colour to its full value. Will you let me know--but this will do at your leisure, for the time has not come yet--whether a picture being painted as I paint mine, exclusively with Bell's medium and turpentine from first to last, and, I may add, worked on up to the last moment of sending in, _i.e._ a fortnight later, may on the walls of the Academy be safely varnished with this new material of yours, either alone or diluted with a little poppy oil? I look forward with interest to Heyl's Madder Green. * * * * * _December 5, 1891._ I shall certainly try the Heyl's Madder Green, which I hear of through you for the first time. Laurie's daffodil cadmium is very pretty. I have got some; but my new delight now is yellow cobalt, which you have found to be absolutely safe, and which is absolutely delightful as a colour. * * * * * My tempera is come from Italy, and I am told that it is made of the tails (feelers?) of the cuttle-fish (sepia). Would you like to look at it again from curiosity? I understand that with the reservation that it darkens, I may use it with impunity in, under, and with the oil--that is enough for _my_ purpose. * * * * * _October 16, 1894._ Will you kindly advise me on the tempera, of which I send a tube? It is used by my friend, Prof. Costa, who gave it me; he likes it vastly. It coalesces _with oil_; he uses it also by itself _between_ two paintings in oil. I have often longed for something to keep down the _greasiness_ and _slipperiness_ of oil paint when correcting or going over a surface often, oil and water _do_ coalesce sufficiently. The most luminous thing I ever painted (and it has stood like a rock) was painted (or certainly _thickly under_painted) with a vehicle made of _starch and oil_. What _this_ medium is, I don't know. Please advise. * * * * * _March 7, 1894._ Forgive secretary again.