76 Scientific Intelligence. 



with niccolite, pyrrhotite, chalcopyrite, etc. It occurs massive 

 and lamellar with occasional octahedral crystals. An analysis 

 by Johnston gave, after deducting 13*55 p. c. Si0 3 the following 

 results: 



As S Ni Fe Co Cu 



46-96 16-71 26-32 790 2 01 010 = 100 



The results of an examination of some thirty nickel and cobalt 

 ores is given. Most of these are identified as pyrrhotite and show 

 amounts of nickel varying from a trace up to 4 per cent. Two 

 nickel minerals from the Vermilion mine. Denison, Algoma, gave 

 respectively 9 - 40 and 40 - 80 per cent of nickel. An analysis is given 

 of the harmotome from the Beaver mine, O'Connor, Thunder 

 Bay. A hygroscopic opal from Savona Mt., B. C, containing 

 7 p. c. H 2 0, lost 3 "25 in a dry atmosphere at ordinary tempera- 

 ture retaining the rest; in a moist atmosphere it regained this 

 and 3-50 p. c. in addition. 



3 9. On the presence of Magnetite in certain Minerals and 

 Rocks. — Prof. Liversidge has undertaken to solve the question 

 as to the cause of the magnetic character of certain minerals, such 

 as hematite, franklinite and others. Upwards of fifty specimens 

 were examined and by the same method in each case, viz : the 

 mass was pulverized finely in a porcelain or agate mortar and 

 then the magnetic portion separated by a rather feeble electro- 

 magnet. The results show that while the magnetic properties 

 of pyrrhotite unquestionably belonged to the mass, as always as- 

 sumed, those of chromite, franklinite, spinel, garnet and some 

 hematite, limonite, and other minerals and rocks examined, were 

 due to scattered particles of magnetite. For example, a dark 

 compact hematite from Elba yielded 15 per cent of magnetite; 

 a specimen of franklinite from New Jersey yielded 32 # 23 per cent 

 of magnetic particles; a chromite from New Caledonia yielded 

 0"7 p. c. ; a number of serpentines gave from a trace up to 14 p. c. 



The author also shows that iron sesquioxide obtained by pre- 

 cipitation from the acid carbonate of iron is magnetic; also that 

 magnetic iron sesquioxide can be obtained by heating' the mag- 

 netic oxide ; further, that ordinary iron rust formed under atmos- 

 pheric conditions by the oxidation of metallic iron is usually 

 magnetic and polar. — Trans. Austral. Assoc. Adv. Science, 1891. 



20. Manual of Qualitative Blowj)ipe Analysis and Determina- 

 tive Mineralogy, by F. M. Endlich. 456 pp. 8vo. New York, 

 1892 (The Scientific Publishing Company). — Dr. Endlich has 

 given us in this volume a very thorough discussion of the subject 

 of Qualitative Blowpipe Analysis, developing the many methods 

 and reactions employed with a fullness which may fairly be said 

 to be exhaustive; a beginner might indeed be pardoned for feel- 

 ing a little overwhelmed by the amount of matter placed before 

 him. The author's wide experience in the use of the blowpipe* 

 has enabled him to discriminate between the many reactions 

 which have been proposed, to develop a number of new ones, and 



