Newton Balance



Newton Balance




The balance is contained in a cage of red-brown wood, atop a glossy black 20mm base made of either ceramic or stone, under which is larger red-brown colored base. Some scuff marks of normal wear and tear appear present on the front face as well as in the top back corners of the wooden cage, possibly from its position against a wall. Three tarnished adjustable feet hold the stand approximately 20mm above the ground, allowing for more precise measurements. In addition to the adjustability of the feet, there is a top-down level built into the glossy black base with which the level of the balance can be measured.

The main access way to the scale is through a glass-paned vertical-lift door approximately 390mm x 215mm. The door is counterweighted and stays open when lifted. A set of strings attaches the door to the frame and prevents it from being completely removed. On the reverse side of the balance an identical door exists and is available to use similarly, however, it is not counterweighted and must be held open.

Below the cage and beneath the glossy black base is a wooden drawer of similar dimensions to the door. A round-tipped tarnished knob is attached via screw to the front face which is used to pull the drawer out. If desired the drawer can be removed from the base entirely. Contained within the drawer is two brushes of unknown type with handles made of worn, rolled plastic.

Also contained in the drawer is a wooden object approximately 76mm x 25mm x 30mm in height. It is unknown the use of this object, however it is a hollow trough shape or wide U with a groove in each vertical wall supposedly to rest an object across. This wooden object is likely composed of three pieces each glued together in this formation. The contents of the drawer also included a ‘Directions’ sheet with instructions on how to carefully set up the balance, as well as general information about the product. This instructions sheet was in a distinctly early 20th century style and, though slightly stained and discolored, was easy to read and understand.

The physical components used for measurement are mostly composed of brass and aluminum, likely with some iron or steel screws used to connect pieces.

The main mast of the balance stood in the middle of the cage and formed the stem of a ‘T’ shape with the other half of the center weighing mechanism. This top section is quite intricate with many parts, where the function or purpose of some remain undiscovered. A focal point of this section is a piece of aluminum with a ten-inch ruler, zero in the middle extending left and right to five inches. Resting on this ruler were very small, light, and thin silvery square arches with a loop on top.

An adjustable bar running across the top of the cage can be used to lift and move these pieces across the scale and remain equidistant apart using two static prongs attached to the horizontally shifting cage-bar. Hanging from each side of the top section of the ‘T’ are the plates for measurement. According to the ‘Directions’ sheet, this balance had a maximum accuracy limit of 200g. The plates hang from S-hooks and, when not resting on supporting fingers, swing freely. Between the plates, screwed into the base of the ‘T’, is an ivory-colored plaque with the words “Made by Newton Balance Corp./-For-/Arthur H. Thomas Co./Philadelphia, U.S.A.”. Above the words are hash marks with a slight upwards curve and, similar to the ruler above, the middle is the resting mark. A downward needle extending from the top section stops in front of these hashmarks and as the scale is used indicates which side is heavier, and by what amount. The hashmarks are approximately 10mm apart with 4 sub-hash marks in between.

To use the balance, the first step is to release the plates from their supports, which is done by turning a knob just above that which opens the drawer counterclockwise. Once the rests have been removed the plates hang freely and the function of measuring can be commenced. This process of measurement was attempted with a selection of objects, however, other than a visual representation of how the mass of one object compared that of another, the ability to use this object as a means of scientific experimentation was unattainable.


Larissa Harris; Mark Franchi




American English


Physical Object


Newton Balance No. 228 - A.H.T. Co., No. 21318


United States of America

Physical Dimensions

Base: 48.8cm x 10.16cm x 23.18cm
Cage: 41.59cm x 36.28cm x 21.59cm


Wood (for the cage), glass or hard plastic base, glass panels, brass, aluminum


Made by the Newton Balance Corp. for Arthur H. Thomas Co., Philadelphia, PA


223 branded into right side, MCMT-9994 plaque screwed in on top


607E Chemical Science and Engineering Building

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Larissa Harris; Mark Franchi, “Newton Balance,” Michigan Tech Inventory of Historic Scientific Instruments, accessed April 17, 2021,