102 HISTORY OF SCIENCE. 



glazes like a man groping in the dark. Not having heard of the way 

 in which glazes were made, I pounded all the substances which I 

 thought might effect anything, and then I bought a quantity of earthen 

 vessels. After having divided these into pieces, I placed upon them 

 the substances I had ground, and having marked them, I made memo- 

 randa in writing of the substances put upon each of them. Then 

 having constructed a furnace to my fancy, I set the aforesaid pieces 

 to bake, in order to see if my stuffs would produce any white colour ; 

 for I did not seek any other than a white glaze, because I had heard 

 it said that the white glaze was the basis of all the others." 



After long years of toil Palissy at length succeeded in attaining his 

 object, and having thus been put in possession of the means of giving 

 technical perfection to his works, his artistic genius came into play in 

 the production of that peculiar kind of ware for which he is so famous. 

 His works are distinguished by natural objects and ornaments in relief, 

 which are often highly coloured. The colours, however, are limited 

 to a comparatively few, of which a pure yellow, an ochry yellow, a 

 greyish blue, and a deep blue are the most frequent ; but some speci- 

 mens show also certain shades of green and violet of great beauty. 

 The truthfulness of the forms of the natural objects which decorate 

 the Palissy ware has often been remarked, and this quality Palissy ob- 

 tained by the simple process of taking casts from the objects, such 

 as fish, reptiles, shells, etc. These casts formed the moulds for his 

 dishes, and, of course, from one set of moulds he was able to produce 

 any number of examples. It is interesting to remark that Palissy took 

 his casts of shells from the fossil specimens iii the tertiary strata of 

 Paris, and that he contributed a most important part to a debate 

 then being carried on among the learned as to the origin of fossils. 

 Palissy, in a treatise on springs and waters, published in 1580, asserted 

 and he was the first in France who dared to do so that the fossil 

 shells and fishes were the actual remains of once living marine animals. 

 He opposed also a doctrine, then much in vogue in Italy, which at- 

 tempted to account for the fossil shells by a universal deluge. 



Alchemists in numbers flourished during the sixteenth century in 

 every country of Europe. Many of these were impostors, who took 

 advantage of the credulity of the age, and avowedly sold " the 

 powder of projection," by means of which, they pretended, base me- 

 tals could be transmuted into silver and gold. Others doubtless there 

 were, but in fewer numbers than in the previous age, who entertained 

 a sincere belief in the possibility of attaining the great object of al- 

 chemy, and these laboured through good report and through bad 

 report to reach the great secret. Many treatises on alchemy belonging 

 to this period are extant ; but though these afford much curious lore 

 to the antiquary, we shall pass them over, and resume the history of 

 chemistry in the following century by a notice of Van Helmont. 



In the laboratories of the alchemists many strange chemical phe- 



