2938-2942 



Muffle Furnaces (draught), for hardening, case-hardening, tempering, assaying, etc. 



The construction of these furnaces is carried out on the latest scientific principles ; the finest quality material 

 and workmanship only are employed. 



The body is erected with strong cast-iron casing, lined inside with non-conducting material, inside which the 

 fireclay body of the furnace is'built. All parts of the furnace are easily detachable. 



These furnaces are specially suited for hard daily use where absolute precision and reliability are required, 

 though where it is necessary to maintain exact temperatures for long periods, the use of a good gas pressure governor 

 with one of our dial-indicator gas taps (designed specially for fine adjustments of gas supply) is recommended. 

 (See Fig. 2931-2937.) 



Lifting counterbalanced door, or loose stoppers, supplied in place of hinged doors, if ordered. 



One fireclay muffle or two fireclay trays supplied with each furnace. 



Cast-iron muffles can be supplied to all sizes, silica muffles for Nos. 2938 to 2941 only. 



With all classes of work in which it is not absolutely necessary to protect the contents of the furnace from 

 the products of combustion, a considerable saving in gas consumption can be effected by substituting a tray in 

 place of the muffle, thereby forming what is commonly known as an oven furnace. For most classes of work for 

 which the oven furnace is suitable, a saving of 25% in gas consumption is effected by this means, and also the cost 

 in renewals of trays is considerably less than that of muffles. 



CROSS STREET HATTCTK GARDETST, E-C 



562 





ml' 



