272 



SCIENCE. 



[N. S. Vol. XII. No. 294. 



of this Department is not so much to get to- 

 gether a large miscellaneous collection of relics 

 as to afford a means of popular instruction in 

 American archteology, it is desired that stu- 

 dents from all parts of the country shall send 

 exhibits or memoranda descriptive of results 

 obtained in their special fields of labor. For 

 example, one exhibit will show the animals 

 domesticated by the Aborigines of the Western 

 Continent, and will explain why the lack of 

 large useful animals capable of domestication 

 hampered the development of civilization in 

 the New "World. 



Through the co-operation of the Department 

 of Agriculture and Horticulture, exhibits will 

 be made of the plants cultivated in both North 

 and South America before the discovery. 



Often the placard is of as great value as the 

 specimen, and one of the features of the ex- 

 hibit will be cases describing in brief various 

 types of stone age implements and the methods 

 of manufacturing them. Any student of Amer- 

 ican archaeology who has elaborated some spe- 

 cial phase of the subject and wishes to place 

 his work before the public may send on manu- 

 script, and placards will be made from it, with 

 due credit to the investigator. 



A. L. Benedict. 



NOTES ON INORGANIC CSE3II8TBY. 



The first installment of the promised revision 

 of the atomic weight of iron by Professor Theo- 

 dore W. Richards has appeared in the Zeitschrifl 

 fur anorganische Chemie, the work being done in 

 conjunction with Dr. Gregory P. Baxter. The 

 method used is the reduction of ferric oxid by 

 hydrogen, the temperature used being 900°. 

 The oxid was formed in two different ways : 

 first, by precipitation from ferric nitrate of the 

 hydroxid, which was dehydrated at 900° ; 

 second, by direct heating of the nitrate at 900°. 

 The first method gave in two experiments the 

 figure 55.90. The series by the second method 

 — five experiments — gave 55.883. This is 

 slightly lower than the generally accepted 

 figure, 56.0, and the paper discusses briefly 

 possible sources of error in earlier determina- 

 tions. Further work on other compounds is to 

 be carried out. 



A FEW years ago Kriiger described a red solu- 



tion formed by leading chlorin into an alka- 

 line solution of copper, which was supposed 

 to contain a salt of a cupric acid. This work 

 has been repeated by F. Mawrow and described 

 in the Zeitsohrift fur anorganische Chemie. So 

 far from getting the above results, a brown 

 powder resulted, having the approximate com- 

 position of 6 CuO, H2O. The proportion of 

 active oxygen was never more than a small 

 fraction of a per cent. , whether the experiment 

 was carried out at a boiling temperature, or 

 cooled by ice. 



In the Annales de chimie et de physique, G. 

 Baudran describes a very considerable series ot 

 'tartar emetics,' double tartrates of metals and 

 alkalies, corresponding to the ordinary tartar 

 emetic, potassium antimonyl tartrate. They 

 are generally formed by dissolving the hydroxid 

 of the metal in tartaric acid, and treating the 

 product with an alkaline tartrate. The emetics 

 of manganese, bismuth, iron, aluminum, and 

 chromium were formed, as well as borotartaric 

 acid and potassium borotartrate. 



As far back as 1829 a salt was discovered by 

 Zeise, formed by the action of alcohol upon 

 platinum chlorid, which he called acechlorpla- 

 tin and to which he gave the formula (in mod- 

 ern nomenclature) KCl, CsH^, PtCl,, H^O. For 

 a few years this compound, combustible chlorid 

 of platinum as it was sometimes called, excited 

 much attention, and Liebig and others attacked 

 unsuccessfully the composition proposed by 

 Zeise ; but standing alone as it did, with no 

 compounds of analogous character, for more 

 than half a century few workers have noticed 

 it, though Birnbaum in 1868 proved the cor- 

 rectness of Zeise's proposed composition. In 

 1844 Eeiset formed a compound by the action 

 of ammonium nitrate on the salt of Magnus 

 which he considered to be platosammin chlorid, 

 Pt(NH3)2Cl2, but which Cossa proved fifty years 

 later was salt of a platosemiammin chlorid, 

 PtNHjClj. Now in the last number of the 

 Zeitschrifl fiir anorganischen Chemie, S. M. Jor 

 gensen, who has so enlarged our knowledge of 

 the platinum and other metallic bases, shows the 

 complete analogy between these salts of Zeise 

 and of Cossa, the latter giving a double alkali 

 salt of formula KCl, NH3, PtClj,H20, which 

 corresponds exactly to a salt of Zeise in which 



