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Scientific Intelligence. 



MgS0 4 'H 2 is produced. Many other cases of this usual manner 

 of transformation are known. The peculiarity to which attention 

 is called is the behavior of certain hydrates which do not act in 

 the usual way in this respect. Three examples are given. Gay- 

 lussite, CaC0 3 \Na 2 C0 3 '5H 2 loses the whole of its water at 100°, 

 while pirssonite, CaC0 3 \Na 2 C0 3 *2H 2 0, does not undergo any 

 change at 100°, and it is only at a temperature of 130° that it 

 loses the whole of its water. The compound Mg 3 (P0 4 ) 2 '22H 2 0, 

 at 100°, quickly loses 18 molecules of water, and then very slowly 

 loses more water, while artificial bobierrite, Mg 3 (P0 4 ) 2 *8H 2 0, 

 does not undergo any alteration at 100°. The arseniate Mg 3 - 

 (As0 4 ) 2 -22H 2 0, corresponding to the above phosphate loses 17 

 molecules of water very quickly at 100°, while artificial hoer- 

 nesite, Mg 3 (As0 4 ) a '8H 2 0, doesnot change atallatl00°. — Bulletin, 

 xxix, 724. h. l. w. 



3. Attempts to Prepare Nitrogen Fluoride. — Several years 

 ago it was announced by Warren that he had prepared a fluoride 

 of nitrogen in oily drops by the electrolysis of ammonium fluoride 

 solution. Moissan failed to produce any such compound by the 

 action of fluorine either on nitrogen or ammonia. Rupp and 

 Geisel have recently attempted to prepare the compound by 

 Warren's method, and by other methods which suggested them- 

 selves, aifd after an elaborate series of experiments were unable 

 to obtain any evidence of its existence. It seems probable that 

 Warren used ammonium chloride, and that the explosive body 

 obtained by him was merely nitrogen chloride. — Berichte, xxxvi, 

 2677. h. l. w. 



4. Quantitative Chemical Analysis ; by the late Dr. C. 

 Remigius Fkesenius. Authorized Translation of the Sixth 

 German Edition by Alfred I. Cohn. 2 vols., 8vo, pp. 780 and 

 1255. New York, 1904 (John Wiley & Sons). — This voluminous 

 work is apparently an absolutely complete translation of the last 

 German edition, w T hich appeared in 1875, twenty-nine years ago. 

 The translator has made a number of additions. In the first part, 

 which is the systematic treatment of the subject, the additions 

 are practically confined to those introduced by Johnson and by 

 Allen, and to be found in the last American edition of 1881. It 

 is to be noticed, however, that modern atomic and molecular 

 weights have been substituted for older ones throughout the 

 work. The second or special part of the book contains occasional 

 additions by the translator of modern methods, and as appendices 

 are added the methods of analysis adopted by the Association of 

 Official Agricultural Chemists, and also Hillebrand's treatise on 

 Rock Analysis. 



It is to be regretted that the translator abandoned his original 

 intention of inserting many of the more recent and improved 

 methods of chemical analysis, for space might have been gained 

 for these by the omission of the antiquated methods thus sup- 

 planted ; but the reverential attitude of the translator was evi- 

 dently such that it seemed improper to omit anything. However, 



