46 ANNUAL OF SCIENTIFIC DISCOVERY. 



stone of flinty hardness. A bushel of completely dried, clean 

 sand, mixed with a small portion of finely ground carbonate of 

 lime (to closely fill the interstices), is worked up in a loam mill 

 with a gallon of the liquid silicate of soda. When thoroughly 

 mixed, the sand is of such a consistence that it can be moulded 

 into any form. In this condition the solution of the chloride of 

 calcium is poured upon the moulded sand ; instantly the silicate 

 of soda and the chloride of calcium mutually decompose each 

 other, and reunite as silicate of lime and chloride of sodium or 

 common salt; the former practically indestructible in the air, and 

 the latter removable by washing. The setting takes place as 

 quickly as with plaster of Paris. As the hardening goes on, the 

 objects are immersed in the solution, for hours if necessary, ren- 

 dered boiling by means of steam. The air is thus expelled. 

 Though water washes out the salt, proving permeability, the 

 stone, when once freed from the salt, is almost impermeable. 

 This artificial stone has been exposed to the extremes of heat and 

 cold, with sudden transition from one to the other, to acids, and 

 to foul gases, with no effect on its structure. In fact, being nearly 

 all silica, it is practically indestructible ; having no oxidizable con- 

 stituent, it is unalterable in the air; and being impermeable, it 

 will not be injured by moisture or frost. It may be used for any 

 purposes of construction or architectural ornament that natural 

 stone can be employed for. It is a discovery of very great impor- 

 tance, and of very extensive application. 



LIQUID STONE. 



The following are extracts from a paper read before tUe Boston 

 Society of Natural History, in March, 1867, by Prof. A. L. Fleury, 

 of New York. 



The liquefaction of* stone, the dissolving of hard refractory 

 quartz or flint, like sugar or salt in water, the preparation of a 

 colorless, mineral, and permanent petrifying liquid by economical 

 means, and on a large scale, is a problem, the solution of which 

 seems to belong to the present progressive century. 



The uses to which a perfect liquid flint, a hydrate of silica, 

 could be turned, are numerous and intLresting, provided the 

 liquid possesses the property of becoming insoluble in water 

 after having been deprived of its water of solution, keeping back 

 its water of crystallization. 



The first idea that suggests itself of the use of such a liquid is 

 the preparation of artificial stones for ornamental and building pur- 

 poses. Should it be possible to produce this petrifying liquid 

 cheap enough, building-stones in all their variety could be made 

 and cemented together with the same petrifying solution. The 

 cost of cast flint-marble statuary, tombstones, baths, tables, 

 mantel-pieces, and ornaments of all kinds, would be, of course, 

 much less than if laboriously cut from the stone, and they come 

 quickly into universal use. In a similar way, as photography 

 now diffuses the masterpieces of the art of painting among all 

 classes of society, and cultivates their taste, the art of casting flint- 



