One Thousand Experiments, 8fc. 359 



in small pieces into a crucible, with 6 parts of powdered chalk, 

 and 6 parts of powdered Hessian crucible-ware. Dispose the 

 whole so that after fusion the iron may be completely covered, 

 to prevent the least contact with the air ; noAv give the crucible 

 a gradual heat, and then expose it to a white heat. Generally 

 an hour will be sufficient to convert two pounds of iron into 

 exceedingly hard steel, capable of being forged ; an advantage 

 not possessed by steel in the usual manner. Observations. — 

 Here the iron is formed into a carburet, by combination with 

 the carbon of the chalk and crucible powder." This is the 

 whole article. We should like to be told what English artisan 

 communicated this process, or at what factory steel is thus 

 made. It is Clouet's old scheme, which no Englishman ac- 

 quainted with steel would practise. 



" Exp. 114. To obtain pure platinum.'' Here we have nothing 

 but Ridolfi's preposterous process, which we trust no artisan 

 in this country has ever practised. 



" Exp. 120. To prepare pure alumine. To a solution of 

 sulphate of alumine (alum) in water, add a solution of pure 

 soda, as long as a white precipitate falls down. Here the sul- 

 phuric acid combines with the soda, leaving the alumine free. 

 Dry the precipitate quickly, and preserve it in a phial." Now, 

 as pure soda is an excellent solvent of alumine, the earth can- 

 not be precipitated " free" in this way. Ammonia is the pro- 

 per precipitant, and the precipitate may be dried as slowly as 

 we please, after it has been thoroughly washed. Our author 

 has here contrived, in the fewest possible lines, to display the 

 greatest possible ignorance of practical chemistry. 



" Exp. 171. Solution not attended with change of hulk. In 

 the chemical combination of fluids with solids, the compovmd 

 occupies no more room than the solvent did previous to com- 

 bination. Put some sugar, muriate of soda (common salt,) or 

 any other salt! into an ounce of water, until no more will be 

 dissolved. The solution will measure just an ounce, as the 

 water did before the addition of the salt ; but although there 

 is no increase of bulk, there is a considerable increase of den- 

 sity and specific gravity." One hardly knows how to treat such 

 edrontery of falsehood, for every assertion here is contrary to 

 the- best established facts, and the plainest experiments. Water 

 saturated with common salt has a specific gravity of 1.1962, 

 and contains 25.5 per cent, of salt. The 74.5 parts of water, 

 in dissolving these 25.5 of salt, whose specific gravity is 2.0,' 

 would, if there were no increase on the bulk of the "solvent, 

 acquire a specific gravity of 1 .342. But the real increase of bulk 

 on these 74.5 parts of the solvent is to 83.6 exactly. Were 

 there not a condensation attending this exertion of chemical 

 aflinity, the bulk of tiie solution would be 87.212. Or, in 

 round numbers, 30 parts by bulk or weight of water, dissolve 



