From Benjamin Dearborn
Boston March 6th 1804
In the late papers some passages have appeared, which intimate, that it is in contemplation to establish a general standard of weights and measures throughout the States. Numerous testimonies of the want of such a standard, and a belief that I can be instrumental in furnishing the means of producing it, have united to influence me in making this communication, which I am solicitous of laying before Congress through your hands, if you think it worthy of their attention.
The testimonies above mentioned, were presented me in a late tour from this to Savannah, in which I made many comparative experiments with the standard weights of different places. In these experiments it was a rare instance to find the standard of any one place, corresponding with the standard of any other; and equally so, to find in any set of standard weights, the necessary correspondence between the Unit and its Component Parts. Most of the standard beams were incorrect as the weights; having one arm longer than the other, with defective construction generally; rendering them unfit for those accurate decisions which are indispensable in adjusting weights. The results of these experiments are so unfavorable to that Uniformity which Ought to exist, that they have led me to contemplate means for obtaining an immutable linear measure, by which standards of length, of weight, and of capacity, may be so constructed as to approach toward perfection, as nearly as can rationally be expected in this imperfect state of being.
For some time past, my attention has been particularly turned to the subject of statics; and by a new application of statical principles I have constructed balances, which are now preferred by our Banks, &c to any instrument heretofore known, for accurate weighing.1 To complete the system for an invariable standard, I have studied the construction of a Time Piece, for ascertaining with exactness the length of a pendulum-rod, which shall vibrate seconds; the rod to be so attached, as to be taken out and exchanged, as often as necessary, whereby to compare the extremes which different climates, or different temperatures of the atmosphere may require.
It is probable that few persons who are in the habits of planning and executing, have studied the above mentioned subjects more fully than myself; and could I render those studies useful to my country, without injury to my family, it would give me pleasure.
Lest an unprotected letter might be rated as a visionary speculation, I enclose a line from the Honble. George Cabott, President of the Boston Branch of the United States Bank, whose judgement is known, but to be admired.2 I have the honor to be very respectfully Sir yr hble servt