Jan., 1912. Annual Report of the Director. 131 



In order to permit turning of the tubes in the case for examination 

 of their contents, the tubes were mounted in racks, connected by belts 

 to pulleys and these to a wheel outside the case, so that the visitor, 

 by turning the wheel, can turn the tubes and thus examine their con- 

 tents in detail. Two cases containing forty tubes each were thus 

 installed and fully labelled. Large additions were made to the series 

 illustrating the use of the by-products of petroleum, these uses having 

 greatly increased in the time that has elapsed since the collection 

 was originally formed. In moving the collection it was necessary to 

 store all of this series, but it will be available for future exhibit. The 

 portion of the collection now on exhibition occupies ten wall cases 

 and two floor cases. It includes 232 specimens of petroleums, 114 

 specimens of lubricating oils, 57 specimens of vaselines and allied 

 products, 40 quantitative specimens, and 80 specimens of oil sands. 

 The series of by-products obtained in the production of coke was in- 

 stalled in uniform sealed glass tubes, in order to insure the preservation 

 of the materials and make a better installation possible. A series of 

 models to represent the development of the blast furnace has been 

 begun by the construction of a model of a modern iron blast furnace 

 and some of its accessories. The design of the model was based upon 

 careful studies made by the Assistant Curator, through the courtesy 

 of the Illinois Steel Company, of furnaces at South Chicago. The 

 model has been built so as to occupy one half of one of the wall cases 

 used for the ores of the base metals. It consists of two equal portions, 

 one showing the exterior appearance of the furnace and accessories, 

 and the other the same in sectional form. All are built on a scale of 

 two feet to the inch. In the group giving the exterior appearance, 

 a tower elevator for bringing charges to the top of the furnace is repre- 

 sented at the extreme right. This is connected by a bridge to a charg- 

 ing platform in the furnace proper. The furnace on the scale mentioned 

 represents one 60 feet in height. The tap hole is in front and the slag 

 eye on the right. At the left is shown a downcomer to carry off the 

 gases and at its base is a self-dumping dust-catcher. At the left of 

 this is a single hot -blast stove with pipes, valves, etc. In the sectional 

 group complete longitudinal sections are shown of the various members. 

 In the section of the furnace the brick work, water-cooling pipes, 

 charging bells and other pipes and valves are shown. A charge of 

 real ore, fuel, etc., is also represented, passing to a molten state at the 

 bottom. The sections of the stove, dust-catcher and downcomer also 

 show full details. In addition to the sectional character of the con- 

 struction above ground, the imder-ground connections and foundations 

 are represented. In the laboratories of vertebrate paleontology the 



