January 25, 1889.] 



SCIENCE. 



55 



the comforts and luxuries of life, there has been, perhaps, nothing 

 more wonderful than the improvements in the methods of obtain- 

 ing and utilizing light. 



As lately as fifty years ago the candle was the chief illuminant in 

 use. This was replaced by the oil-lamp, which was undoubtedly a 

 great step in the way of progress. A little later this luxury made 

 way for gaslight. But progress could not stop here. Having been 

 educated to a proper appreciation of good light, the public, not sat- 

 isfied with this improvement, demands that gas, in turn, shall make 

 room for some other agent. The electric light has proved itself the 

 only agency for the accomplishment of the difficulty of still further 

 improvement. 



Among its manifold advantages are, — 



The great superiority and steadiness of the light. 



It does not over-heat the atmosphere, nor charge it with poison- 

 ous gases, while depriving the air of its life-sustaining element, 

 oxygen. 



It also removes all danger to life and health caused by the es- 

 cape of gas. 



Ventilation, a matter of such vital importance to health and life, 

 thus becomes a comparatively simple matter, the difficulties in this 

 direction no longer increasing in inverse ratio to the amount of light 

 used, as with gas. 



The safety it offers over every other form of light, removing the 

 ever-present danger of fire, by doing away entirely with the use of 

 the match. By simply touching a button or turning a switch, any 

 designated light or all the lights in a house can be lit from any part 

 of the building. They also admit of a much more advantageous 

 distribution of light. 



The cost of insurance where electric light is used is in all cases 

 reduced. 



Its freedom from smoke and deleterious gases, which work such 

 incalculable destruction to ceilings, walls, decorations, books, paint- 

 ings, etc., makes its adoption the greatest possible saving. But, 

 great as has been its success, its introduction into general use has 

 been limited, as it has not been placed within the reach of all. It 

 has been shut out from the very place where good light is most 

 needed and appreciated, " at home," owing entirely to the method 

 of producing it, — that of lighting direct from a dynamo. 



The electric lighting of houses distant from a central lighting- 

 station has heretofore, to a certain extent, been an impossibility, 

 owing chiefly to the fact that a steam-plant has been necessary, and 

 that in the production of electric light direct from a dynamo it has 

 been impossible to obtain light except when the dynamo is run- 

 ning. 



The operation of a steam-engine necessitates the presence of an 

 ■experienced engineer, which immediately makes its production so 

 expensive as to be beyond the reach of any but the more wealthy. 



The time when light is most required in a private house is be- 

 tween the hours of six and ten or twelve o'clock at night, when it 

 is almost impossible to obtain the services of a competent engi- 

 neer. 



The noises and vibrations attending the operation of a steam-en- 

 gine have been another drawback to its introduction, for few are 

 willing to have machinery in operation in a private house until after 

 the hour of midnight or during the time when light is required. 



There has been no means of producing electric light with the 

 direct lighting method so that light may be available at all times 

 except by the running of a dynamo continuously, and, unless light 

 can be available at all times, it fails to compete with gas. 



The storage-battery, however, seems to overcome all these diffi- 

 culties, and to solve the problem of incandescent lighting in iso- 

 lated cases. 



In the course of some remarks recently made before an electric- 

 light association by a prominent New York electrical engineer, the 

 importance of storage-batteries in electric lighting was very clearly 

 shown in the following : " I would call the attention of the members, 

 for instance, to the lighting of private residences which are detached, 

 country residences, summer residences, and large mansions. I be- 

 lieve that here the storage-battery has a sphere which it will hold 

 as its own, for the reason that the direct system of lighting of to- 

 day does not afford all the requisites of a perfect application of 

 electricity for lighting. It has not supplanted gas, and you will find 



that wherever isolated plants are in use to-day they still have gas. 

 Now, I do not consider that we can look upon isolated lighting as 

 a success until we see it drive gas out altogether. To do that, we 

 must have electricity ' on tap ' for twenty-four hours a day, the 

 same as gas, and I can conceive of no system by which this can be 

 done successfully except one involving the use of storage-batteries 

 as an accessory, if nothing more." 



A storage-battery can be charged with the use of almost any 

 form of power during the hours of the day, and in many instances 

 energy now running to waste may be utilized in laying up a supply 

 for night use. 



One of the interesting developments in this connection is the 

 prominence of the gas-engine as a producer of electric light. This 

 power seems to be particularly fitted for work in connection with 

 storage-batteries. The operation of these engines is so simple that 

 they can be cared for and run by the employees of almost any 

 house. The power is always available. The gas in the engine is 

 ignited by a spark from the battery, and, in fact, can be started by 

 simply turning a battery switch, using the dynamo for a moment 



iits?i:. 



THE JULIEN 



as a motor to bring the engine up to speed. Thus by the simple 

 operating of a switch the entire plant is set in motion. The battery 

 is charged during the day, and at night, when the engine is shut 

 down, enough energy will have been stored to supply the house 

 with light for the entire night. 



The accompanying illustration represents one of the most inter- 

 esting displays at the American Institute Fair this season, the in- 

 stallation of the Julien Electric Company, showing the application 

 of storage-batteries to the lighting of private residences in connec- 

 tion with a Baldwin gas-engine and a United States dynamo. The 

 plant consisted of a 4-horse-power gas-engine coupled to a 30-Hght 

 dynamo and 36 cells of Julien battery. There were in the exhibit 

 some 95 i6-candle-power lamps, in addition to two i-horse-power 

 electric motors used for operating a fan and sewing-machine, — 

 another application to family needs. The current from the battery 

 can also be used for pumping water, the running of electric bells, 

 burglar alarms, and other light work. The dynamo charges 

 the battery during the day ; and at night, when the full number 

 of lights is turned on, the dynamo takes care of 30 lights, and 

 the remaining 65 are taken from the accumulators. It will thus 

 be seen, that, in addition to serving as a reservoir to be called 

 on when the plant is not in operation, by the running of the dyna- 

 mo, and at the same time discharging from the battery, a largely 

 increased number of lamps is available, thus reducing very con- 

 siderably the amount of power necessary to be introduced. It is 

 generally acknowledged that light derived from storage-batteries is 

 of greater steadiness than that produced direct, thus increasing con- 

 siderably the life of the lamps. 



