Unpublished paper, 'On certain molecular changes which occur in steel and iron, during the separate acts of heating and cooling' by [Richard Hill] Norris

Description

Norris explains that in the course of certain researches in physiological physics with which he had been engaged, it became necessary to inquire into the nature of a fact which was observed by George Gore, and published in volume 17 of the Proceedings of the Royal Society as 'A Momentary Molecular Change in Iron Wire'. In this communication it was shown that if a strained iron wire were heated to redness by a voltaic current or other means, on being allowed to cool, the contraction of cooling was at a certain point, and for a limited period, arrested by an action of elongation. 'With wires of iron 0.65mm thick and 21.5cm long, strained to the extent of ten ounces or more, and heated to full redness, the phenomenon was clearly developed. For example, the needle of the instrument went with regularity to 18.5 of index-plate; the current was then stopped; the needle instantly retreated to 17.75, then as quickly advanced to 19.75, and then went slowly and regularly back, but not to zero. After shutting off the source of heat, the wire contracted 0.75mm, and then expanded 2mm; so that it returned 1.25mm beyond the original point of heating, and then resumed its course towards zero, which it failed to reach. The length of the kick, plus the amount of stretch, occasioned during the occurrence by the strain was therefore 2mm. If the temperature of the wire was not sufficiently high, or the strain upon the wire not enough, the needle went directly back without exhibiting the momentary forward movement. The temperature and strain required to be sufficient to actually stretch the wire somewhat at the higher temperature. A higher temperature with a less degree of strain, or a greater degree of strain with a somewhat lower temperature, did not develop the phenomenon. The wire was found to be permanently elongated on cooling.' Norris explains how he aimed to construct experimental apparatus of much greater delicacy and heating power than that used by Gore, and presents observations based on the results of his experiments.

Marked on front as 'Archives Jan 17/78'.

Subject: Chemistry / Physics

Received 15 August 1876. Read 12 April 1877. Communicated by Gore.

Whilst the Royal Society declined to publish this paper in full, an abstract of the paper was published in volume 26 of the Proceedings of the Royal Society as 'On certain molecular changes which occur in iron and steel during the separate acts of heating and cooling'.

Reference number

AP/59/6

Earliest possible date

1876

Physical description

Ink on paper

Page extent

139 pages

Format

Manuscript