V. MANUFACTURES. 641 



2589. Mica-plates used for effecting fusions and for evapo- 

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



Mica is not affected by most acids. This material may also he employed as 

 a cheap substitute for platinum in many chemical operations. 



2590. Mica Powder, for use in filtrations. 



Max. Raphael, Breslau* 



2591. Mica-spectacles, for use in laboratories, to protect the 

 eyes in all operations when dangers from spitting or from explo- 

 sions have to be guarded against. Max. Raphael, Breslau. 



2594. Ozone generating Tube, provided with drying appa- 

 ratus. C. Kramer, Freiburg, Baden. 



2547 'a. Fairley's simple form of Ozone Generator in 

 Glass. Harvey, Reynolds, and Co. 



2577. Hydrofluoric Acid Apparatus, in lead. 



F. A. Wolfffy Sons, Heilbronn and Vienna. 

 For the use of public laboratories. 



2557. Collection of Glass Stop-cocks of various sizes. 



Ch. F. Geissler $ Son, Berlin. 

 2581. Collection of Glass Stop-cocks. 



Dr. H. Geissler, Bonn. 



2602. A. Mitscherlich's Apparatus for the continuous 



evolution of chlorine gas, together with a water bath having a 



constant water level. Prof. A. Mitscherlich, Miinden. 



This apparatus is described in A. Mitscherlich's chemical publications, part 2, 



p. 6. 



1377c. Apparatus for the Production of Hydrogen Gas. 



Alvergniat Freres, Paris. 



V. MODELS, DIAGRAMS, APPARATUS, AND CHE- 

 MICALS EMPLOYED IN OR RESULTING FROM 

 CHEMICAL MANUFACTURES; ANALYTICAL AP- 

 PARATUS USED IN MANUFACTORIES. 



2566b. Patent Platinum Apparatus. 



Johnson, Matthey, and Co. 



Newest form for the concentration of sulphuric acid, securing great 

 strength, productive power, safety and economy in working, and highest 

 degree of purity of acid, with a minimum of platinum : 



40075. S s 



