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New Zealand Times, Volume XXXVII, Issue 8342, 31 January 1913, Page 10

In a paper on “ The Present Status of the Temperature Scale,” communicated to the Eighth International Congress of Applied Chemistry, held in New York in September, Dr G. K. Burgess, of the Bureau of Standards, pointed out that the advance in exact measurements, and the present state of our knowledge of the gas laws, permitted the expression of temperatures in terms of the thermo-dynamic or ideal gas-scale, to which the usual gas-scales approximated so closely that it was, for most purposes, not necessary to distinguish between them. The radiation laws, in terms of which extrapolation to the highest temperatures was made, were likewise based on this thermodynamic scale. Yet the corrections to be applied to the scales given by gases were not known with complete certainty, especially for very low temperatures (for such, hydrogen and helium thermometers were used, in particular) and for very high temperatures. For temperatures above 450 deg. Cent, nitrogen at constant pressure was used, but there was so far no international agreement as to really high (nor as to very low) temperatures. For these regions the thermometric scale was more readily realised by the radiation laws of Wien and Stefan, although the char-, acteristic constants of these laws again were not sufficiently determined.