[D8836AAB], Letter from Edison Lamp Co, Francis Robbins Upton to Thomas Alva Edison, February 1st, 1888


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[D8836AAB], Letter from Edison Lamp Co, Francis Robbins Upton to Thomas Alva Edison, February 1st, 1888

Editor's Notes

I spoke to you the other day regarding the naming of machines of their Watt capacity. You said, you thought they should be named by their Lamp, capacity. I have spoken to several regarding this matter and it is the impression, that those competent to buy electrical plants, or to contract for them, have now attained and sufficient knowledge of the business to know that we cannot change the capacity of the machine by re-naming it; and that it is much simpler, and better, to claim that our lamps are more economical, and require a certain amount of energy; thus stating the exact facts of the case. ### The advantage of calling machines by their Watt capacity instead of by their lamp capacity, or a number, which means little, is largely in the fact that by so doing, lamps may be used of different candle power, or of different economy; and by reckoning up the Watts that each style of lamps takes, until the maximum Watts of the machine is reached. As it is now, a machine is said to be be good for so many lamps; this means, so many 16 C.P. lamps, reckoning 3.1 Watts per candle. If 20 candle power lamps are sold to a plant there is an uncertainty as to what is meant by "Lamps"; whereas, if Watts are frankly stated, as is done when the size of engines are stated, so that the parties can figure out the power form the pressure of the steam, and the length of the cut-off, it brings the business into a thoroughly comprehendable shape. ### This may seem to be a trivial matter; but I feel, that the business has reached a stage, when thorough rankness in stating electrical and engineering facts should be, as far as possible, the general policy. The calling machines by their capacity is one step towards a simplification of the business; it is a similar step to that which has been made, when engines were sold by the size of their cylinders, and not by calling them certain horse power; or when wires are sold by their diameters, in thousand of inches, and not by an arbitrary number. It tends to remove the mystery from dynamo machines, and makes them simply commercial articles of certain definite capacity. Yours truly Francis R. Upton [Marginalia: "Ans Feb 7[2?]/88"] see response dated 2 Feb 1888 D8836AAB




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