Scientific Intelligence, 



n channres 



1 the coherent form by fusion in hydrogen. 



ithod of analysis is given on the supposition that all the above met- 

 . sent. It may generally be much abridged, as the ore is seldom of 

 ) complicated a character. Jf there is a difficulty in procuring perfectly 



ent through the liquid, using platinum 



r spongy s 



I have not been 



I by hydrogen. The c 



the strength of the current. I have not been very successful m 



; before complet 



this experiment, that, with a longer tube in proportion to the quantity of ma- 

 terial, kept at a good heat throughout its length, this plan might give good 

 results, the metal being considerably less volatile than the oxyd. 



Mr. Crookes adds the following description of thallium and its chemi- 

 cal reactions and compounds, whicli we copy in full i"rom his paper. 



Thallium in the pure state is a heavy metal, bearing a remarkable resem- 

 blance to lead in its physical properties. Its specific gravity is, however, 

 higher—about 12. The freshly scraped surface has a brilliant metallic lustre 



metal. It is very soft, being readily cut with a knife and indented with the 

 nail ; it may also be hammered out and drawn into wire, but has not much 

 tenacity in this form, 

 ness, and with care several [ 

 lump. There is, however generally f 



oxydation. The metal itself does not appear to be sensibly volatile ueju" - 

 red heat. I have made no special attempts at present to determine the atomic 

 weight, although from two estimations of the amount of sulphur in the sulpmd 

 it appears to he very heavy. The figures obtained did not, however, agree 

 well enough to enable me to speak more definitely on this point, than that 1 

 believe it to be above 100. I may mention that I obtained this element in the 

 pure metallic state and exhibited it to several friends as early as January last, 

 and should then have published an account of it. had it not been for the rea- 

 sons already mentioned. Thalliii 



Oryds of Thallium.— ThaWmm forms two, and probably three oxyds: one 

 possessing basic properties, which I shall call the oxyd; another containing 

 more oxygen, possessing acid properties, which may therefore be called tbalJic 

 acid ; and most likely a third, or suboxyd, which forms the first portions of the 

 precipitate formed by zinc in solutions of this metal ; the first action being a 

 darkening of the solution, and the production of a deep-brown powder, wHicn 

 by longer contact with zinc turns to a dense black precipitate. , . . 



Upon carefully evaporating the nitric acid solution upon a water bath, bat 

 not carrying it to dryness, a mass of deliquescent cr}'stals is obtained on cool- 

 ing, which are decomposed upon addition of water with separation of a wliue 

 or pale-yellow precipitate, which appears to be a subnitrate, and an acid solu- 

 tion containing nitrate of thallium. If the liquid is evaporated quite to dryn^ 

 and kept at a temperature of 100° C. for a little time, the nitric acid goes oB, 



f thallic acid. 



