108 



Scientific Intelligence. 



grain of phosphorus in 5 ounces of matter. When the mass contains 

 much phosphorus the distillate contains phosphorous acid, which is easily 

 oxydized and detected. The author found that phosphoric and phos- 

 phorous acids do not pass over when distilled carefully with water. A 

 fresh human stomach boiled with water gives no soluble phosphates ; on 

 the other hand a stomach in a state of decay yields to water phosphoric 

 acid which can readily be detected by ammonia and magnesia. — Chem- 

 isches Central Blatt. No. 8, 113, Feb. 20, 1856. 



5. Sulphate of Nickel. — Marignac finds that the quadratic sulphate 

 of nickel contains but 6 equivalents of water instead of *i as formerly 

 asserted. The rhombic (trimetric) crystals contain V eqs. of water, and 

 are isomorphous with the sulphates of zinc and magnesia ; they crystal- 

 lize from a pure solution at from 15° to 20° C. Thus quadratic crystals 

 separate at a temperature of from 30° to 40°, the monoclinic crystals 

 between 50° and 70°. The monoclinic crystals also contain 6 eqs. of 

 water. When the rhombic crystals pass in the sunlight into the quad- 

 ratic form, they lose 6*40 per cent, water. The monoclinic crystals re- 

 main transparent above 40° C. ; at ordinary temperatures they become 

 gradually opaque without loss of water and pass into the quadratic form, 

 It is therefore proved that there is no trimorphous sulphate of nickel, 

 and that it is only the sulphate with 6 eqs. of water which is dimorph- 

 ous. Solutions of sulphate of magnesia at 70°, sulphate of zinc from 50 & 

 to 55°, and sulphate of cobalt from 40° to 50°, gave crystals with 6 eqs, 

 of water isomorphous with the monoclinic sulphate of nickel. — Ann. der 

 Chemie und Pharmacie, xcvii, 294, 



6. Specific volume of compounds containing Nitrogen. — Kopp has pub- 

 lished a brief notice of his researches upon this point, and finds that the 

 specific volume of nitrogen in the volatile bases is 2'3 ; that of cyanogen 

 in the cyanids 28 ; and that of N04 in the nitro compounds 33. The 

 empirical laws which Kopp has discovered for the compounds of carbon 

 and hydrogen, or carbon, hydrogen and oxygen, hold good also for bodies 

 containing nitrogen, so long as these bodies belong to the same group, 

 If we recognize in the different types a real difference of internal consti - 

 tution, the consideration of the specific volume affords a good means of 

 determining to what type a body belongs. Thus from their spec. vols, 

 it appears that the nitrites of the ethyl series belong to the type of 



C4H& ) H ) 



hydrogen and not to that of water. Nitrite of ethyl is -^-q 4 y like g y , 



C4H5 ) H ) 



and not y O2 like jj y O2. In other words, the nitrite of ethyl 



C4H5 ) 



bears the same relation to the nitrate r O2 which the cyanid of ethyl 



ol]^ 5 I does to the cyanate q^J 5 j O2. The author promises to consider 



the subject more fully hereafter. — Ann. der Chemie und Pharmacie, 

 xcvii, 374. 



1. On the specific heat of some elements and on the isomeric modifica- 

 tions of Selenium. — Eeonault has published an interesting and valuable 

 addition to his former researches on specific heat, and has now determined 

 this important physical constant for several of the rarer elements. The 



