554 SEC. 13. CHEMISTRY. 



2573. Bunsen's Cathetometer. Julius Schober, Berlin. 



2574. Habermann's Air-bath. Julius Schober, Berlin. 



2575. Filtering Apparatus, provided with a glass receiver 

 and 2 india-rubber rings and supports. 



F. A. Wolff Sf Sons, Heilbronn and Vienna. 

 This filtering apparatus is intended for the use of schools. 



2576. Water Vacuum Pump, constructed for a fall of water 

 of at least 20 feet. F. A. Wolffs? Sons, Heilbronn and Vienna. 



This pump is of simple construction and great solidity. Any desired 

 vacuum may be obtained by making use of a regulator. 



2577. Hydrofluoric Acid Apparatus, in lead. 



F. A. Wolff 'fy Sons, Heilbronn and Vienna. 

 For the use of public laboratories. 



2578. Collection of Burettes and Burette Stands. 



Dr. H. Geissler, Bonn. 



2579. Collection of Pipettes, with stand. 



Dr. If. Geissler, Bonn. 



2580. Collection of small Glass Apparatus for the Estima- 

 tion of Carbonic Acid. Dr. H. Geissler, Bonn. 



2581. Collection of Glass Stop-cocks. 



Dr. H. Geissler, Bonn. 



2582. Collection of Thermometers. 



Dr. H. Geissler, Bonn. 



2583. Knop's Azotometer, as modified by Dr. Wagner. 



Ehrhardt and Metzger, Darmstadt. 

 Accompanied by a descriptive price list. 



2584. Instrument for Calculating Atomic and Volu- 

 metrical combinations, to 4 places of logarithms. 



Rudolph FFeber, AscTiaffenburg. 



2585. Drying-closet, provided with mica-plates, for watching 

 the drying of precipitates obtained in quantitative chemical 

 analysis (see Mineralogy). Max. Raphael, Breslau. 



2586. Mitscherlich's Apparatus for organic analysis by 

 means of mercuric oxide. Professor A. Mitscherlich, Miinden. 



The apparatus is described in Mitscherlich's paper entitled " Organic 

 " Analysis by means of Mercuric Oxide," published by E. S. Mittler and Son, 

 Berlin, copies of which accompany the apparatus. 



2587. Mitscherlich's Metal Dryhig Closet, with acces- 

 sories. Professor A. Mitscherlich, Miinden. 



