Taylor.] ^^-^ [Oct. 21, 



So early in our national existence as the year 1790, the illustrious Jeflfer- 

 son, then Secretary of State, in obedience to a resolution of Congress call- 

 ing upon the Secretary to propose a plan or plans for establishing uni- 

 formity in the currency, weights, and measures af the United States, pre- 

 sented a report recommending a decimal system of metrology, and its 

 derivation from a natural and permanent standard of length. 



Instead of taking the ordinary pendulum of 39 inches, he proposed the 

 second's rod of 5 feet, then generally known as Leslie's pendulum rod. 

 A simple straight rod, without the bob or ball, suspended at one end, has, 

 as is well known, its centre of oscillation at a distance of two-thirds of its 

 length from its point of suspension ; or, in other words, is one-half longer 

 than the common loaded pendulum vibrating in the same time. Such a 

 rod vibrating seconds is 58.72368 inches long ; dividing this into five equal 

 parts, Mr. Jefferson took this fifth part, or 11.744736 inches as the length 

 of the new "foot," and from this by decimal multiples and subdivisions 

 he presented a series of tables of weights and measures. 



When we reflect that the system of metrology here displayed was per- 

 fected by Mr. Jefferson before any steps had been taken by the French 

 government toward the decimal re-organization of weights and measures 

 in that country, we must regard it as a memorial in the highest degree 

 creditable to the judgment and contriving skill of its author ; and as one 

 of many illustrations of the varied activity of his mind, and of the in- 

 terest he ever felt in all schemes for human improvement. The great 

 superiority of his proposed scales of measure, to those in common use, 

 cannot be questioned ; and their adoption would have been a signal public 

 benefit. The tables presented by him form a connected and complete sys- 

 tem, each depending directly upon the one preceding, and necessarily 

 flowing out of it, and all determined from a single and invariable natural 

 standard by a very simple and beautiful mode of derivation. 



In this respect, however, the French system is by far the best of all that 

 have yet been devised. Starting with a carefully measured quadrant of 

 the earth's meridian, and dividing it into ten million parts, this system 

 presents us with a "metre "* as a universal standard to which all others 

 may be referred. Indeed, if a decimal system of weights and measures is 

 to be ultimately adopted, there appears to be none that has such just 

 claims to our acceptance as that of the French ; and although it would be 

 much more difficult of popular introduction than a simple decimalization 

 of our own divisions, and therefore less "practicable," there can be no 

 doubt that it would be in every way superior, both in regard to the pre- 

 cision of its measures, and the simple and philosophical character of its 

 divisions ; besides all which it has the immense advantage of being already 

 introduced and in successful practical operation throughout the great Re- 

 public of France ; and every extension of its use would be an important 

 step in the progress toward a uniform system among all nations. 



* Equal to 39.3707SS inches ; very nearly the length of the second's pendulum, and not 

 much longer than our yard. 



