##
Mathematical Charts and TablesTables for Monetary Transactions

**Tables for Monetary Transactions**

American merchants, bankers, and employers have used a wide range of tables to ensure the accuracy of monetary transactions. Some of these tables were produced for stand–alone use, while others were designed to aid those calculating with machines.

As early as 1812, Joseph Jelleff of New York State patented a disc with printed scales used for interest calculations. Versions of this instrument sold at least into the 1830s. William B. Leavitt of New Hampshire copyrighted a similar wooden instrument in 1845. A few years later, Samuel S. Young of Ohio patented a linear instrument for interest calculations. In 1867, Albert Pierson of New Jersey patented a rather different device, in which the tables were mounted on rotating prisms, for the same purpose. Manufacturers of computing machines, such as Felt & Tarrant Manufacturing Company of Chicago and the Marchant Calculating Machine Company of California distributed interest tables to assist those using their products.

Those assessing and paying taxes also used tables. In 1879, Robert Levin Mudd, a county clerk in Illinois, patented a device to ease the work of correctly accessing taxes. In the 1930s, New York entrepreneurs introduced the Costometer, which was designed in part to assist in calculating newly introduced Social Security taxes. Tables also were used for computing both markups and discounts on goods sold, and for finding the total cost of sales, as when multiplying the rate of shipping freight per pound by the number of pounds shipped. Sometimes it is unclear precisely why units used were chosen, as in a handwritten multiplication table collected from a Massachusetts manufacturer of shuttles for looms.

"Mathematical Charts and Tables - Tables for Monetary Transactions" showing 2 items.

## Mathematical Table, Pierson Machine For Calculating Interest

- Description
- In the 19th century, several American inventors devised moving tables that allowed one to calculate interest. This is the U.S. Patent Office model for a device designed to calculate the amount of interest upon any amount less than one thousand dollars for any number of days less than eighty-five at two rates, six and seven percent. It was invented by Albert C. Pierson of Rahway, New Jersey.

- The instrument has three ten-sided rotating prisms, with the sides of each prism marked at the top with the digits from 0 through 9. The rightmost prism represents units, the middle one tens, and the leftmost hundreds in the amount of money borrowed or lent. Each side of each prism has two columns of 84 numbers, corresponding to interest charges for 1 to 84 days. The left column has interest charged at 6%, the right at 7%. Setting the prisms to the correct amount and then summing the numbers on the three prisms for the appropriate number of days gives the interest. A rotating strip on the left allows one to determine the number of days between two dates of the year.

- This is the model for the first of two patents taken out by Albert C. Pierson (probably 1836–1870). Both relate to calculation.

- Reference:

- A. C. Pierson, “Improvement in Calculating Machines,” U.S. Patent 62,882, March 12, 1867 (the machine illustrated by this model).

- A. C. Pierson, “Improvement in Calculating Machines,” U.S. Patent 73,995, February 4, 1868.

- Location
- Currently not on view

- date made
- 1867

- patentee
- Pierson, Albert C.

- maker
- Pierson, Albert C.

- ID Number
- MA*252689

- catalog number
- 252689

- accession number
- 49064

- Data Source
- National Museum of American History, Kenneth E. Behring Center

## Rotating Mathematical Table, Sinclair's Freight Computer

- Description
- By the late 1860s, railroads were vital to American commerce. This is the U.S. patent model for a rotating multiplication table used to compute freight charges. It was patented by Albert Sinclair of West Waterville, Maine, in 1869.

- The instrument has a cylindrical metal case painted black, with metal feet at each end. The case contains a rotating cylinder covered with a printed table of numbers, which represent amounts charged for shipping given quantities of freight at given rates. A long narrow opening across the case shows one line of this table. The rate charged (from 1 to 50 cents per hundred pounds) is given at the far left of the table, with total fees indicated for weights from 1 to 9, 10 to 100 (by tens), 200 to 1,000 (by hundreds), and 10,000 to 50,000 (by ten thousands) pounds. A paper sticker glued above the window lists these weights, as well as the cost of shipping the weights for rates of 1/4 cents, 1/2 cents, and 3/4 cents per hundred pounds. Such costs are added on to the figure shown in the table if the rate is not a whole number.

- A blue paper sticker pasted to the case below the window gives instructions. A mark on it reads: SINCLAIR'S FREIGHT COMPUTER (/) FOR RAILROADS AND GENERAL FREIGHTING BUSINESS, (/) By the use of which, all multiplication and division in computing Freight is dispensed with. A reward of Ten Dollars is offered to the first person who can find an error of one cent in the computation of this machine or table.

- Albert Sinclair also took out a patent for a broom earlier in 1869. The 1870 U.S. Census lists an Albert Sinclair, boardinghouse keeper, living in Lewiston, Maine, with his wife, Martha, and several children. Lewiston is about fifty miles southwest of Waterville. The 1860 census lists this Albert Sinclair and his family as living in Kalmar, Minnesota, where he was a farmer, thirty-nine years old, and born in Maine.

- References:

- U.S. Census records.

- Albert Sinclair, “Broom,” U.S. Patent 92,483, July 13, 1869.

- Albert Sinclair, “Improvement in Price-Calculating Devices,” U.S. Patent 97,974, December 14, 1869.

- Location
- Currently not on view

- date made
- 1869

- patentee
- Sinclair, Albert

- maker
- Sinclair, Albert

- ID Number
- MA*252696

- accession number
- 49064

- catalog number
- 252696

- patent number
- 97974

- Data Source
- National Museum of American History, Kenneth E. Behring Center