April 1, 1864.] THE TECHNOLOGIST. 



THE PALAIS DE L'lNDUBTRIE, PARIS. 399 



lime, like most of that obtained by calcining shells, is of a peculiar fine- 

 ness. Its alkaline properties are very prominent, and hence it is preferred 

 for absorbing the acids in the sugar manufacture. Guiana possesses 

 also rich sulphur mines, different sorts of earth, fit for excellent pottery, 

 and for polishing metals, ferruginous kinds of sand, the melting of 

 which gives a greyish, fine-grained, and shining mass. We would direct 

 attention to the specimens of porcelain clay which comes from the 

 numerous and important stone pits of Point a Pitre. In Guadaloupe 

 it is used for different purposes, but its import in quantity to Europe 

 yields an immense profit. At the present day the best quality is sold 

 in Brest at 9fr. the cubic-metre, a price considerably lower than that 

 of the porcelain clay, which comes from Auvergne and Italy. The 

 island of Bourbon is celebrated for a beautiful red porcelain clay, 

 but the great distance will scarcely allow of its lucrative import into 

 Europe. 



In passing, we cast a hasty glance at the mineral waters of Mar- 

 tinique, and on the different stones and minerals of New Caledonia. 

 The copper mines of Ambriz and Loanda are well known, and con- 

 siderable masses of copper and malachite are annually imported thence 

 into England. Fine specimens of talc, which is found alternating 

 with felspar, are sent from Guiana: this colony exhibits also some 

 beautiful specimens of iron and gold, the nuggets of the latter being of 

 considerable size. Senegal also possesses gold strata, which promise a 

 rich profit. They are found in the province of Damhagnagney, not far 

 from the famous cataracts of Felon, the limit of navigation on the river 

 Senegal. This region has been but recently explored ; and the know- 

 ledge we yet possess of this fertile district is not very extensive. 

 On entering another room, we perceive specimens of fibres and textile 

 substances, and among these a beautiful collection of cottons. A few 

 remarks on this valuable plant may not be out of place. At the 

 present day, when, through the American war, the scarcity of this pro- 

 duction becomes more and more sensible, it is undoubtedly of the 

 greatest importance that our minds should be occupied with the cultiva- 

 tion of this plant. In general, a cultivation so simple does not require 

 much attention, and could open new sources of wealth to several of 

 the French colonies. The landowners of the Antilles would certainly 

 obtain better results from the cultivation of the cotton-plant than they 

 do from their large sugar plantations. The most beautiful long-fibred 

 varieties of cotton seem to be indigenous here, and Mr. Aubry-Lecomte, 

 the intelligent curator, declares the Antilles to be the true native 

 country of the cotton-plant, by showing us that it grows not only spon- 

 taneously upon the mountains, rocks, and sea-shores, but that the 

 varieties cultivated here are also the most esteemed. The avarice, how- 

 ever, of the proprietors, the import of inferior varieties, the bad selec- 

 tion of seed, and divers commercial frauds, have all contributed to destroy 

 this element of commercial welfare in its germ. At the commencement 



