ELECTRIC LIGHT IX THE COUNTRY HOUSE. 



109 



few. The output of the dynamo when the engine gives i.l h.p. is four hundred watts, as ahvadv 

 mentioned, and, making allowance for the efticiencv of the accumulators, we can obtain this for three 

 halfpence per hour. Metallic filament lamps can now be obtained to give one candle-power per watt, 

 so that four hundred watts is sufficient for forty ten-candle-power lamps, and these can be used for an 

 hour at the cost of three halfpence for fuel. In the house we have under consideration the maximum 

 output with all the lamps in use would be about live hundred and fifty watts ; but the switching on and 

 off of electric light is such a simple matter that servants and others are less likely to keep the lamp&amp;gt; 

 burning uselessly than they would be with other forms of illuminant ; we may, therefore, safely assume 

 that the total number of lights will never be on at once. If we assume an average lighting time of four 

 hours per day throughout the year, and allow that something less than half the number of lamp-, arc 

 burning for this time, we can fairly take our fuel cost at three farthings per hour. Of course, this implio 

 care and economy in the use of the light ; but there should be no difficulty in obtaining this average it the 

 necessity of switching off, whenever possible, is duly impressed on the servants. Ihis for lour hours on 

 each of three hundred and sixty-five days brings the total cost of our fuel for the year to one tliou&amp;gt;and 

 and ninety-five pence, or four pounds eleven shillings and threepence. There are. of course, other thm^ 

 to be considered besides cost of fuel, such as attendance, lubricating oil and maintenance ol the generating 

 plant and accumulators ; but the two latter items should not exceed the cost of the fuel, and, as far a-^ 

 attendance goes, the gardener, if an intelligent man, could easily be trained to attend to the plant. 



Where there is a chauffeur, minor repairs in connection with the plant and installation naturally 

 become part of his work. The experience gained in dealing with the various lorm&amp;gt; (it electric ignition 

 apparatus used on the modern motor-car implies a rudimentary knowledge ol the electric circuit. This 

 will save calling in an electrical contractor in many cases where it would be otherwise ne vs&amp;gt;ary. Y\ e 

 see. therefore, that if we allow live per cent. intere&amp;gt;t on the capital outlay, the total cost of lighting Midi 

 a house as that shown in the plans would not exceed seventeen pounds per annum when all allowances 

 had been made ; surely not a very high price when the c!canline and hygienic properties of electric 

 light are dulv considered. M.U Kin-. HIKP. 



135. FIRST FLOOR PLAN. 



