38G PURPLE DYEING, ANCIENT AND MODERN. 



melted together, and kneaded under water. By this process the fine powder i9 

 washed out, and in time siidvs as a sediment in tlie liquid. The mineral yields 

 not more than one-fourth of its weight of coloring material. 



Up to a very recent time Italy continued to be the chief, as it had been the 

 original, manufactory of ultramarine, and thence the finest shades were derived. 

 The tediousness, the difficulty, and, consequently, the costliness in both time 

 and money of the old process of producing ultramarine from the Lapis lazuli, 

 naturally excited great desire among scientific chemists to find some cheaper 

 and readier artificial means of producing that color, doubly precious to the 

 painter for its beauty and its permanency ; but so invariable from different 

 causes v.^ere the failures of all attempts in that directioii that the solution of the 

 problem was well nigh despaired of, when hope was as suddenly as accidentally 

 revived. In 1818 it happened that in France a sandstone furnace for the melting 

 of soda was taken down, and a beautiful colored substance, never seen there be- 

 fore, was discovered. It was remarked, that formerly the furnace for the melting 

 of soda had always been constructed, not of sandstone, but of brick. The mass 

 of matter thus discovered was examined by Vauqueliu, who observed in its 

 appearance and composition points of great resemblance with ultramarine ; btit 

 still no clue offered itself to guide him through the perplexities of the investi- 

 gation. Similar observations were made in other soda manufiilctories, as, for 

 instance, by Hei-raann, in Schoubeck, Avho had thrown away above a hundred 

 weight of the colored mass found in a similar furnace when the latter was pulled 

 down ; and by Kuhlmann, at Lille. We shall not venture to decide whether or 

 not the " blue material," mentioned by Goethe in his " Italian Travels," (1781,) 

 as being taken from limekilns in Sicily, and used for the adornment of altars 

 and other objects, was homogeneous with this product of the soda furnace, and 

 whether both were, in fact, an artificially and accidentally produced ultramarine. 



The question still remained uhanswercd, how was this substance in the case 

 of each furnace produced ? In what did it originate 1 At length, in 1828, the 

 solution of this important question Avas found and published by Professor C 

 Gmelin, of Tuebingen. During eighteen years he had been occupied with 

 researches on the "Lapis lazuli" and its kindred minerals, the products of the 

 volcanic eruptions of Vesuvius. Reflecting on the recent circumstance, he was 

 led to believe that, notwithstanding there had been so many unsuccessful 

 attempts, the production of an artificial ultramarine Avas not an impossibility. 

 Furtlier study of the natural coloring substance disclosed to him the sulphurous 

 portion of the components, and holding that clue he at length succeeded in 

 producing a most brilliant ultramarine. 



At about the same time, another German chemist, the well-known " Doebe- 

 reiner," had a glimpse of the true nature of the coloring principle of ultramarine. 

 He was the fii'St positively to assert that it was to be attributed to sulphur alone. 

 He obtained, however, a mere glimpse of this beautiful discovery, other occupa- 

 tions preventing him from following it up. A very few more experiments, and 

 he would have been completely in possession of it. Gmelin was scarcely more 

 successful, though the absence of this additional jewel in his scientific crown 

 was owing to a diff"ereut cause. It is not in the nature of a true savant to 

 place his talent at usury, or, in plainer terms, "to make money by it;" though 

 now and then doubtless, in these days of extravagant projects, it is not impos- 

 sible to find a savant at the head of some speculating manufactory, to the 

 success of which his reputation gives a substantial guarantee. Men of science 

 of this kind are certainly much souglit after by industrial speculators, yet the 

 exceptions do not greatly affect my assertion as to the general disinterestedness 

 in this respect of the German savant.* He, for the most part, when, in the 



* This characteristic is by no means confined to German savants, but is stared by most 

 men of science in all countries. 



