510 SEC. 13. CHEMISTRY. 



2450c. Drawing of Bull's Patent Kiln. 



Hermann Wedekins. 



2451. Model of " Weldon " plant for the regeneration of Black 

 Oxide of Manganese in the Manufacture of Chlorine. 



Professor Roscoe, F.R.S. 



2452. Model of the Chemical Laboratory of the Secondary 

 Town School, Leyden. Constructed by J. Noest, custodian of 

 the building. 



Dr. D. de Loos, Lecturer on Chemistry, and Director of the 

 Secondary Town School, Leyden. 



A. Forcing-pump. The pump fills a large cistern in the upper part of the 

 building. This cistern discharges its contents into the white pipes, and 

 supplies the laboratory and the other parts of the building with water. The 

 red pipes carry off the drainage from the laboratory into a sink constructed 

 below the surface. The large black pipes, as also the small ones over the 

 pupils' work-tables, are the gaspipes. 



B. Register-school. 



C. Chimney with three passages ; one to conduct off the smoke of the 

 stove, the others to cany off the bad gases disengaged in chemical operations. 



D. Pump for rain-water and well-water. 



E. Cupboards for twenty-two pupils, in which they keep the re-agents ; the 

 largest, which is open, is for the use of the lecturer on chemistry. 



F. Drawer for small apparatus, as spoons, glass tubes, &c. 



G. Small cupboards for the use of the pupils, in which to keep chemical 

 preparations still in progress. 



H. Bunsen's pump to filter under a lesser pressure. The water, running 

 through the red pipe from the top to the bottom of the laboratory, carries the 

 air from the bottle along with it. 



I. Entrance to the balance-room. 



K. A collection of implements for performing chemical experiments. 



L. Large cupboard for chemical preparations and apparatus. 



M. Table with apparatus for blowing glass. 



2453. Diagram of Carre's Ice-making Machine, by Mr. 



Hubertus Sattler. Dr. Alexander Bauer, Vienna. 



Adapted to be used for making experiments at lectures on technical chemis- 

 try to small audiences. 



2454. Apparatus for Gas Analysis. By M. Orsat, of 

 Paris. Robert Galloway. 



The apparatus is so constructed as to be readily available for the use of 

 ordinarily intelligent workmen, and to furnish not only ready but compara- 

 tively trustworthy indications. 



2455. Apparatus for the Analysis of Gases. 



E. Frankland, F.R.S. 



Several of the mechanical arrangements of this apparatus were first em- 

 ployed in an instrument invented by Messrs. Regnault and Eeiset, but the 

 principles involved in the determination of the gaseous volumes are different 

 in the two instruments. 



2455a. Apparatus for showing the Decomposition of 

 Steam by the Heat of Electric Sparks. 



Professor Frankland, F.R.S. 



