Accession No

0624

Brief Description

Maxwell’s dynamical top, attributed to Charles Ramage, Scottish, c. 1857

Origin

Scotland; Aberdeen [based on attributed maker]

Maker

Ramage, Charles [attributed]

Class

physics; demonstration; games;

Earliest Date

1857

Latest Date

1857

Inscription Date

Material

metal (brass, steel); stone (agate); wood (2 types); paper

Dimensions

box breadth 247mm; depth 227mm; height 201mm

Special Collection

Robert Whipple collection

Provenance

Purchased by Robert Stewart Whipple from H. Dickson, 6 Crammer Road (?), Cambridge, on 25/08/1930.

Inscription

Description Notes

James Clerk Maxwell’s dynamical top, by Charles Ramage, Scottish, c. 1857.

Circular brass base into which a brass pillar is screwed. Concave top to pillar with central agate cup. A bell shaped top with a central steel axle, with sharp tips at both ends, sits on the agate cup and spins gyroscopically to demonstrate the motion of the Earth. The axis carries 2 weights for adjusting the centre of gravity and 9 brass screws around the base of the bell to make fine adjustments to the balance of the top. Wooden handled brass cup for steadying the axle while setting the top in motion. Wooden box with brass hinges and hook fastener, lined with paper and with shelf carrying fitted parts for bell, pillar and handle. Paper label on lid of box reads ‘Clark Maxwell’s Precession Dynamical Top and Accompanying Paper Bound and Lying Beside It. I.D.H.D.’

Bound paper: On a dynamical top, for exhibiting the phenomena of the motion of a system of invariable form about a fixed point : with some suggestions as to the earth's motion / by J.C. Maxwell.

Complete.

References

Events

Description
While a Fellow at Trinity College, James Clerk Maxwell designed this model based on a child’s spinning top. The bell-shaped piece spins on top of the axle. The axle has two weights for adjusting the centre of gravity. The brass screws around the bell are for making fine adjustments to the balance of the top. Maxwell commissioned a number of tops from Charles Ramage to give as gifts.

The Dynamical Top demonstrates the phenomenon of precession. The Earth’s axis of rotation wobbles under the gravity of the Sun, Moon and other planets, just as the spinning top wobbles as it spins. This means that, from the point of view of Earth – and very, very slowly – the position of the north and south celestial poles appear to move in circles against the background sky, and the position of the Earth in its orbit around the Sun, at specific points like the equinox, shifts.
26/02/2025
Created by: Hannah Price on 26/02/2025

Description
A lifelong fan of physics lessons embodied in toys and games, James Clerk Maxwell tackled the question of the motion of the Earth by turning to dynamic tops as models. As he put in in his 1857 paper ‘On a Dynamical Top’, “No illustration of astronomical precession can be devised more perfect than that presented by a properly balanced top”. This argument was substantiated by the production of a number of precision tops—manufactured by the Aberdeen instrument-maker Charles Ramage—for use in his own lectures, for gifting to “various parties who teach rigid dynamics”, and for distributing to “various seats of learning”.

This top is believed to be one of these original Ramage-made devices.
07/01/2016
Created by: Joshua Nall on 07/01/2016

FM:44358