"Its inconveniences were such that tempera was not unreasonably preferred to it for works that required careful design, precision, and completeness. Hence the Van Eycks seem to have made it their first object to overcome the stigma that attached to oil-painting, as a process fit only for ordinary purposes and mechanical decorations. With an ambition partly explained by the previous coarse applications of the method, they sought to raise wonder by surpassing the finish of tempera with the very material that had long been considered intractable. Mere finish was, however, the least of the excellences of these reformers. The step was short which sufficed to remove the self-imposed difficulties of the art; but that effort would probably not have been so successful as it was, in overcoming long-established prejudices, had it not been accompanied by some of the best qualities which oil-painting, as a means of imitating nature, can command."—Ib. p. 88.
116. It has been a question to which of the two brothers, Hubert or John, the honor of the invention is to be attributed. Van Mander gives the date of the birth of Hubert 1366; and his interesting epitaph in the cathedral of St. Bavon, at Ghent, determines that of his death:—
"Take warning from me, ye who walk over me. I was as you are, but am now buried dead beneath you. Thus it appears that neither art nor medicine availed me. Art, honor, wisdom, power, affluence, are spared not when death comes. I was called Hubert Van Eyck; I am now food for worms. Formerly known and highly honored in painting; this all was shortly after turned to nothing. It was in the year of the Lord one thousand four hundred and twenty-six, on the eighteenth day of September, that I rendered up my soul to God, in sufferings. Pray God for me, ye who love art, that I may attain to His sight. Flee sin; turn to the best [objects]: for you must follow me at last."
John Van Eyck appears by sufficient evidence to have been born between 1390 and 1395; and, as the improved oil-painting was certainly introduced about 1410, the probability is greater that the system had been discovered by the elder brother than by the youth of 15. What the improvement actually was is a far more important question. Vasari's account, in the Life of Antonello da Messina, is the first piece of evidence here examined (p. 205); and it is examined at once with more respect and more advantage than the half-negligent, half-embarrassed wording of the passage might appear either to deserve or to promise. Vasari states that "Giovanni of Bruges," having finished a tempera-picture on panel, and varnished it as usual, placed it in the sun to dry—that the heat opened the joinings—and that the artist, provoked at the destruction of his work—
"began to devise means for preparing a kind of varnish which should dry in the shade, so as to avoid placing his pictures in the sun. Having made experiments with many things, both pure and mixed together, he at last found that linseed-oil and nut-oil, among the many which he had tested, were more drying than all the rest. These, therefore, boiled with other mixtures of his, made him the varnish which he, nay, which all the painters of the world, had long desired. Continuing his experiments with many other things, he saw that the immixture of the colors with these kinds of oils gave them a very firm consistence, which, when dry, was proof against wet; and, moreover, that the vehicle lit up the colors so powerfully, that it gave a gloss of itself without varnish; and that which appeared to him still more admirable was, that it allowed of blending [the colors] infinitely better than tempera. Giovanni, rejoicing in this invention, and being a person of discernment, began many works."