This promises the remedy for the disease, as it were, of vehicles, the not drying from the bottom, which will delight every artist, if he finds it a practical truth. We confess, we somewhat fear the sanguine temperament of the translator of Theophilus, and should have preferred some proof to the bare assertion that the picture by John Bellini, in the National Gallery, was painted in amber varnish. Nor can we quite trust his translation of the recipe for making this amber varnish. We were startled with this account of 1 lb litharge to 1 lb linseed oil and 4 ounces of amber--is he correct in translating _spigelhors_ litharge? It should be rosin. With regard to the value of amber varnish, Mr Eastlake quite agrees with Mr Hendrie. Another important improvement of the Van Eycks was the substitution of calcined white copperas for litharge. In a note, Mr Eastlake gives the information that on experiment it has been proved that oil does not take up any portion of the copperas, which nevertheless renders it very drying and hard, but that oil does take up sugar of lead. It should be added, however, that he does not think lead so prejudicial to colours as some have thought it to be. The value of Mr Eastlake's book chiefly consists in the documentary evidence which is now brought to bear upon the question of vehicles; and doubtless, that which is subsequent to the time of Van Eyck is by far the most valuable. Evidence is produced not only of oils in use, and the methods of purifying them, but of varnishes, and recipes for making them, likewise of the colours used. There is yet, however, much untold with regard to the Italian practice, concerning which Mr Eastlake proposes to treat in a second volume. Yet, with regard to the Italian methods, we are not left without some important knowledge, which, however, must be considered as offered rather incidentally; for the Italians having modified, and in some respects much varied the vehicle they derived from the Flemish masters, their methods were again partially adopted by the latter; so that the methods of these two great schools of art could not be kept entirely separate.