I02 Field Museum of Natural History — Reports, Vol. V. 



being supported on a pivoted brass arm in such a manner that it can be 

 moved by the visitor in a semi-circle about the lodestone. The attrac- 

 tion of the lodestone causes a reversal of the ends of the needle and a 

 constant pointing of the needle towards the stone, thus illustrating its 

 permanent magnetic properties. In Skiff Hall, a number of additional 

 collections have been installed, space for introduction of new material 

 having been gained by removal of some previously exhibited. In place of 

 two cases of onyx, the case of products of coal received from the London, 

 England, Gas Light and Coke Company was installed. This case con- 

 tains over 200 large and showy specimens representing the products of 

 coal, such as coke, ammonia compounds, carbolic acid, prussiates and 

 cyanides, creosotes, dyes and pigments. The whole makes a brilliant 

 and instructive exhibit and one of special interest at this time, since the 

 domestic production of many of these compoimds has become desirable 

 in view of the difficulty of obtaining them from abroad. The exhibit is 

 installed in a case received from the London Company, some alterations 

 having been made in it to make it harmonize in appearance with the 

 other cases in the hall. To other collections in the hall a large number 

 of additions have been made, chiefly of material received from the 

 Panama-Pacific International Exposition. The greatest of these addi- 

 tions has been made to the tin ore collection. The additions include 

 the splendid series of South African tin ores obtained through the gener- 

 ous efforts of Mr. W. J. Chalmers, about an equal ntunber of BoHvian 

 tin ores, 15 specimens of Australian tin ores and some tin ores from 

 scattering localities. Owing to increased interest in timgsten ores, this 

 collection also was completely rearranged, and a full series from most 

 of the important localities producing such ores at this time was pro- 

 cured and exhibited. The collection of gold and silver ores of Ontario 

 has been reinstalled with the addition of specimens representing several 

 of the newly discovered gold districts. Part of the copper ore collections 

 have been revised, with the addition of specimens representing the 

 ''porphyry" ores of the United States, and typical ores of copper 

 mining districts of Bolivia, South Africa and China, A series of 

 Chinese ores has been added to the iron ore collection. Specimens 

 from the Panama-Pacific International Exposition and from the mate- 

 rial received from Mr. W. J. Chalmers have been installed with 

 the ores of gold, silver, lead, tungsten, and mercury, thus materially 

 strengthening these collections. A collection from the potash deposits 

 of Utah illustrating the ores and their altuninum salts which are their 

 by-products, has been installed with the alimiintim ores collection. A 

 complete skeleton of the American camel Oxydactylus longipes, of 

 the lower Miocene period, was installed in a floor case in Hall 36. 



