H.A.EVEIJETH 



ONE of the largest electrical goods 

 manufacturing corporations in the 

 country has an elaborate display of its 

 products in the Manufactures Palace. 

 Among the constituent parts of this ex- 

 hibit are several which prove of special 

 interest to the layman. In one glass case 

 are a score of incandescent lamps repre- 

 senting the gradual advance made in the 

 development of this product. The first 

 lamp is one originally produced by Mr. 

 Edison in the year 1880. The filament is 

 of carbonized bamboo and is fastened 

 to its feed wires by means of two minute 

 metal screws and clamps. The latter are 

 soldered to the feed wires and their jaws 

 clamp the filament terminals when the 

 screws are set. Sufficient current is fed 

 to the lamp to maintain the filament at 

 a dull red color, for great care is taken 

 not to burn it out. The last lamp of 

 the series is one of the latest nitrogen- 

 filled products. Near by the visitor will 



see the largest incandescent filament 

 lamp yet produced. It has a candle- 

 power of seven thousand, and, with the 

 aid of a reflector, produces an intense 

 white light of extraordinary brilliancy. 



To illustrate the high tensile strength 

 of a tungsten filament, an exhibit has 

 been prepared wherein a 6o-watt lamp 

 is shown supported by the tungsten fila- 

 ment of a loo-watt lamp in such a man- 

 ner that it is free to oscillate when acted 

 upon by the air currents in the building. 

 A thread of tungsten 0.005 i ncn m diam- 

 eter will support a ten-pound weight, 

 while the tensile strength of this metal is 

 600,000 pounds per square inch. It is 

 so hard that it cannot be machined and 

 must be fashioned by a process of grind- 

 ing. 



The chief feature of the exhibit is the 

 Home Electrical, a ten-room house elab- 

 orately furnished, and fitted with every 

 type of electrical apparatus which could 

 be of possible use in such an establish- 

 ment. The house is a marvel of sim- 

 plicity and cleanliness and strikingly 

 illustrates the usefulness and necessity 

 of electrical energy as a medium for 

 light, power and heat in the modern resi- 

 dence. This captivating Home Electri- 

 cal is burglar-proof in that the doors 

 and windows are fitted with burglar 

 alarms, and a "master switch" is located 

 near the head of the bed in the master's 

 bedroom. By means of the latter the 

 lights over the entire house may be 

 thrown on ; to the ineffectiveness of their 

 associative switches and consternation 



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