Certificate for standard thermometers supplied from Kew Observatory to Joule. Signed by "Welch", shows corrections to be applied to the scale readings.
Former references: Lowery ref. 11; Pate ref. 668.
Certificate for standard thermometers supplied from Kew Observatory to Joule. Signed by "Welch", shows corrections to be applied to the scale readings.
Former references: Lowery ref. 11; Pate ref. 668.