[D8624O], Letter from John H Vail to Thomas Alva Edison, December 28th, 1886


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[D8624O], Letter from John H Vail to Thomas Alva Edison, December 28th, 1886

Editor's Notes

The new lamp will be a big thing, even did it save in copper only. ##Just compare the figures. [Chart showing difference new lamps would make in copper savings in Laramie, Wyoming Territory and St. Paul, Minn.] ##Now take Engines on basis of 1,000 16 cp lamps. [Charts showing savings due to being able to use smaller engines and dynamos.] ##The great benefits which we will derive from the new high economy lamp, when applied in our central stations, will perhaps be better appreciated by a careful perusal of following figures. ##Let us take a full central station of capacity for 2,000 lamps of 16 cp. [Shows estimate for capitalization and disbursement of capital. Then calculates expenses and earnings for such a station, calculating gross earnings, gross expenses, and net profit.] ##We will now assume that the former station, $70,000 capacity being in operation, purchases a complete outfit of the new lamps, and connects on more consumers, up to its full capacity on the new basis, and in the same proportion as the former basis. The Earnings and Expenses would be then as follows. [Calculates new earnings and expenses, showing new gross earnings, gross expenses, and net earnings. Earnings increase by 11.1% by using new lamp.] ##We will now show the increased earning capacity, which could be effected I the Boston Station. [Goes through specifics of Boston station and how earning capacity could be increased.]







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Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University
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