36 



NATURE 



\_May ii, 1S82 



the mildness of the winter of 1881-82 has only been twice 

 exceeded, viz. in 1789-90, when it was 4°'2, or o 0- i more, 

 and in 1778-79, when it was 5°'2, or i c- l more. The 

 winter of 1845-46 showed the same excess as last winter. 



We also gather from the table that these winters, which 

 gave a mean excess of 3°'o, were immediately followed 

 by summers warmer than usual, the mean six months' 

 excess being about a degree (o 0- 8). Indeed, of the whole 

 seventeen summers, only one, viz. the summer of 1790, 

 can be considered as showing a deficiency of temperature 

 sufficiently great and prolonged to be regarded as attended 

 with serious consequences to agriculture. The table is a 

 striking general confirmation of the prognostic long and 

 widely entertained that a mild winter is the precursor of 

 a fine warm summer. 



SEVRES PORCELAIN AND SCIENCE 

 '"PHAT the French should know better than any other 

 *■ nation how to enlist art in the service of science 

 is just what might be expected. Such a service on 

 the part of art to science is only a fair return for the 

 immense resources which scientific research has been able 

 to place at the disposal of art. Nowhere have the dis- 

 coveries of science been more useful or more utilised than 

 at the celebrated porcelain manufactory of Sevres, and 

 the illustrations which we give to day will afford some idea 

 of the beautiful results which are thus produced. As 

 a permanent record of successful scientific efforts, nothing 

 could be more satisfactory and appropriate. In Fig. 1 the 

 characteristic features of the Arctic regions are rendered 

 with almost perfect success and truthfulness ; while the 

 allegorical representation in Fig. 2, in commemoration of 

 the last transit of Venus, is happy in conception, and 

 charming in effect. Of the artistic merits of the two 

 vases our readers can judge for themselves. It may be 

 interesting to give some idea of the difficulties attending 

 the manufacture of such delicate productions, which we 

 are able to do, from a lecture by M. Ch. Lauth, Ad- 

 ministrator of the Sevres manufactory, published in La 

 Nature, to which journal also we are indebted for our 

 illustrations. 



Fig. 1 represents a vase which has been presented to 

 King Oscar of Sweden, and is one-eighth of the original 

 size. The splendid vase represented in Fig. 2 is still only 

 in course of execution, and when complete will be placed 

 in the Mazarin Gallery of the French National Library ; 

 it will be ten times the size of the illustration. M. 

 Lauth thinks the national institution at Sevres should 

 be organised more as a school for the training of 

 workers in the delicate art, than as a mere manu- 

 factory. The art of fixing colours on pottery, M. 

 Lauth tells us, differs essentially from that which deals 

 with the colouring of any other medium. There is 

 required in the materials perfect adhesion, absolute re- 

 sistance to atmospheric influences, and a brilliancy which 

 will make the colours seem part of the object itself. As 

 the colours must be subjected to a very high temperature, 

 there must be eliminated from the palette of the ceramic 

 artist all organic colouring matter, and all the unstable 

 mineral colours ; he must have recourse to oxides, metallic 

 silicates, or to metals. And the fixation of these colours 

 is always the result of a chemical action, of a combination 

 which takes place at a high temperature between the 

 body of the porcelain and the matters used in its decora- 

 tion. Many different methods are used for the purpose, 

 but they are divided into two great classes— decoration at 

 great heat, and the decoration by muffle, an oven of a 

 special kind. 



The former consist: in applying to the porcelain, 

 colouring substances, which are fixed and developed at 

 the same temperature as that at which the porcelain is 

 baked ; this is how the most valued results are attained ; 

 as the enamel covers the colour.it assumes an extreme' 



brilliancy and depth— it becomes part and parcel of the 

 object itself. This is how the magnificent blue of Sevres 

 is obtained, as well as certain browns and blacks, and a 

 few other combinations. The colours may be either mixed 

 on the paste, or put upon the object when moulded, 

 before enamelling, or mixed on the object itself when 

 complete ; they may be also applied to porcelain already 

 baked, which may be again baked at the higher tempera- 



Fig. i.— Sivres Vase 



mkjOldU). 



he X. rlh-Eait Voyage of Baron 



hire. This is notably the process employed at Sevres 

 for their blues. One of the most brilliant varieties ot 

 decoration at high temperature consists in what is called 

 the process of pdfes if application. This method con- 

 sists in painting by the brush on porcelain un- 

 baked or heated ; by successive and carefully adjusted 

 applications, a very great thickness is attained, by sculp- 

 turing which the artist can give the decoration a re- 



