Collections Menu

Date: 1930-1960

Inventory Number: 1997-1-1630a

Classification: Demonstration Apparatus

Subject:

Maker: American ?

Cultural Region:

Dimensions:

0.5 cm (3/16 in.)

Description:

A demonstration device consisting of two glass disks pressed together with the narrow space between them containing a chamber partially filled with mercury.

The mercury chamber is in the shape of the squares that are made by using each of the sides of a right triangle at the center of the demonstration device, with the largest of the squares connected to the other two ones at its corners. The space around the chambers and the triangle at the center have green-tinted glass, while the glass of the mercury chambers is transparent.

The device has a small black base that fits into notches at the bottom and also at the top of the disk.

The mercury chamber is in the shape of the squares that are made by using each of the sides of a right triangle at the center of the demonstration device, with the largest of the squares connected to the other two ones at its corners. The space around the chambers and the triangle at the center have green-tinted glass, while the glass of the mercury chambers is transparent.

The device has a small black base that fits into notches at the bottom and also at the top of the disk.

Signedunsigned

FunctionThis is a device to visualize the pythagorean theorem: in a right triangle, the area of the square made by the hypothenuse is the same as the sum of the areas of the squares made by the catheti. Since the depth of all the chambers is the same, this means that the mercury needed to fill the two smaller square chambers is the same amount that fills the larger square.

When put upside down (there is a notch for the base at the top), the mercury will flow from the two smaller squares and fill the larger one exactly.

When put upside down (there is a notch for the base at the top), the mercury will flow from the two smaller squares and fill the larger one exactly.

Copyright © 2017 The President and Fellows of Harvard College | Privacy | Accessibility | Report Copyright Infringement