III. Some Thoughts on a Coinage, [ca. March 1784]
III. Some Thoughts on a Coinage
[ca. Mch. 1784]
Some Thoughts on a Coinage, and the Money Unit for the U.S.
 1. The size of the Unit.
 2. It’s division.
 3. It’s accomodation to known coins.
 The value of fine silver in the Unit.
 The proportion between the value of gold and silver.

 The alloy of both 1. oz. in the pound. This is Brit. standard of gold, and Fr[ench]. ecu of silver.
 The Financier’s plan.
 A table of the value of every coin in Units.
Transition from money to weights.
 10 Units to the American pound. 3650 grs.=152 dwt. 2 grs.=7 oz. 12 dwt. 2 grs.
Transition from weights to measures.
 Rain water weighing a pound, i.e. 10 Units, to be put in a cubic vessel and one side of that taken for the standard or Unit of measure.
 Note. By introducing pure water and pure silver, we check errors of calculation proceeding from heterogeneous mixtures with either.
Transition from measures to time.
I find new dollars of 1774,80,81 (qu. Mexico Pillar) weigh 18 dwt. 9 grs.=441 grs. If of this there be but 365 grs. pure silver, the alloy would be of 2.1 oz. in the ℔. instead of 19 dwt. the common Spanish alloy, which is 1 dwt. worse than the Eng. standard. Whereas if it is of 19 dwt. in the ℔. troy, it will contain 406 grs. pure silver. The Seville peice of eight weighing 17½ dwt. by Sr. I. Newt’s assay contained 387. grs. pure silver. The Mexico peice of 8. [weighing] 17 dwt. 105/9 grs. (alloy 18 dwt. as the former) 385½. The Pillar peice of 8. [weighing] 17–9 (alloy 18 dwt.) 385 ¾. The old ecu of France or peice of 6. gold Tournois is exactly of the weight and fineness of the Seville peice of 8. The new ecu is by law 1. oz. alloy, but in fact only 19½ dwt. 19 dwt. 14½ grs. pure metal is 432 ¼ grs.
Dollars  Weight  In Water  Loss 
†1773  17–8½  15–15  1–17½ 
†1774  17–8  15–14  1–18 
†1775  17–8½  15–15½  1–17 
1776  
1777  
†1778  17–9½  15–16  1–17½ 
†1779  17–9½  15–16  1–17½ 
†1780  17–10  15–17½  1–16½ 
†1781  17–8½  15–15½  1–17 
1782  
† These average 417. grs. weight in air 41.3 grs. loss in water i.e. 1/10 or more nearly 1/10091 or ten times the weight of water. 
Cassini makes a degree in a great mile contain
miles  D 
69  864 = 365,184 feet 
Then  a geographical mile will be of 6086.4 feet 
a Statute mile is 5280 f. 
A pendulum vibrating seconds is by Sr. I. Newton 39.2 inches = 3.2666 &c. feet
Then a geographical mile of 6086.1. f. = 1863.4 second pendulums.
Divide the geometrical mile into  10.  furlongs 
each furlong  10.  chains 
each chain  10.  paces 
Then the American mile  = 6086.4 f.  English =  5280 f. 
furlong  = 608.64 f.  =  660 
chain  = 60.864  =  66 
pace  = 6.0864  fathom =  6. 
A rod vibrating seconds is nearly 58 ½ inches.
MS (DLC); entirely in TJ’s hand; undated and erroneously placed with the rough draft and notes of TJ’s report to the House of Representatives of a plan for establishing uniformity in currency, weights, and measures, 4 July 1790; MS is in DLC: TJ Papers, 233: 41972.
1. Thus in MS TJ meant 100/1009.