New Patents. 397 



Hyposulphmic acid dissolves carbonate of cadmium : the salt 

 formed is crvstallizable, very soluble and deliquescent ; its taste is 

 astringent ; it contains water of crystallization, the quantity not de- 

 termined. 



Hyposulphuric acid forms three compounds with lead. The neutral 

 salt is obtained by treating carbonate of lead with hyposulphuric 

 acid. It is very soluble, has a very sweet taste, but rather astrin- 

 gent. Its crystals resemble those of hyposulphate of lime and strontia. 

 It contains 15'95 per cent of water. When into a solution of this 

 salt ammonia is poured, in less quantity than required to precipitate 

 the whole of the lead, very small crystals of a subsalt are deposited, 

 which are but slightly soluble in water : these when treated with ex- 

 cess of ammonia are converted into a fine powder, which is still 

 more insoluble. By exposure to the air they both absorb carbonic 

 acid : the first appears to be a compound of one atom acid, two atoms 

 oxide, and two of water ; the second of one atom acid, ten atoms 

 oxide, and twenty-five of water. 



Hyposulphate of copper, prepared in the same way as that of iron, 

 is readily soluble in water, but insoluble in alcohol. When heated 

 it decrepitates, and by exposure to the air effloresces. It has usually 

 the form of quadrangular prisms ; it contains 2547 per cent of water. 

 When the solution is treated with a small quantity of ammonia, a 

 blueish green subsalt is separated ; this does not acquire carbonic 

 acid by exposure to the air : when heated, its colour becomes first 

 green, and then ochrey ; after calcination, it dissolves with a blue 

 colour in muriatic, nitric, and sulphuric acids, and also in ammonia. 

 It is no longer soluble in water, but combines with altering its colour 

 to blue, if the water is cold, and greenish blue, if hot. 



Hyposulphate of cobalt is of rose-red colour, unalterable in the air, 

 very soluble in water, and contains 32*54 per cent of it. 



Hyposulphate of silver crystallizes in octagonal prisms. It is ob- 

 tained by treating carbonate of silver with hyposulphuric acid. At 

 a temperature of 6" it dissolves in two parts of water, unalterable in 

 the air, and contains 8*95 per cent of water; this salt combines with 

 ammonia ; the compound is but slightly soluble, and readily obtained 

 in crystals. — Ann. de Chivi. etde Pliys. Jan. 1829. 



LI.ST OF NEW PATENTS. 



To A. Daninos, of Leman-street, Goodman's Fields, for an in- 

 vention, communicated from abroad, for the manufacture of improved 

 hats and bonnets in imitation of Leghorn straw hats and bonnets. 

 — Dated the 5th of February, 1829. — 6 months allowed to enroll 

 specification. 



To J. Burgis, of Maiden-lane, Covent Garden, for a mctliod of 

 gilding woven fabrics in burnished and dead or matted gold or silver, 

 and which fabrics may be used as gold or silver and hiced border- 

 ings, &c. — 5th of February.— 2 months. 



To R. Green, of HIackwall, for improvements in the construction 

 ofuiu.Hts. — 5th of February. — 1 months. 



To W. H. Kitclien, of High-street, St. Giles's, liloomsbury, and 



.\. .Sinitli, 



