THE note that appeared in NATURE of March 7 A (p. 14) about the nomenclature of temperatures in centigrade degrees measured from a zero 2730 below the normal freezing point of water invited further contributions on the subject of units, and other circumstances transform the invitation into an imperative demand. The report of Sir J. J. Thomson's Committee on Science Teaching, without making a definite recommendation for the adoption of metric units, deliberately adjusts its scheme of education in suchr a way as to make familiarity with metric units a pant of general education. What is the use of doing so if metric units are not to be used for the practical affairs of life? Our present situation is ridiculous. Every boy and girl at school who “does science “now learns that metric units are the universal medium b£ scientific expression, and is practised in their use. At the same time, we cry out for more science in our practical life. What can we expect from our appeal? A boy goes home at the end- of term and tells his father that he has been doing science, weighing in grams, measuring lengths in centimetres, pressures in“millimetres of mercury, and temperatures in degrees centigrade. Surely the most natural remark for any naturally minded parent- to make is that his boy need not pay any attention to that, because, if it had any bearing at all upon practical life, he would certainly have been taught to use pounds or grains, inches, and Fahrenheit degrees, and not the outlandish things that nobody uses after he has left school. There is a story told of Adams, the astronomer, who, in a Swiss hotel, asked for a bath, and was particular that the water should be at ioo°. After a long time, the maid came and said she had done her best, but she could not get it above 950; and I doubt if, even at this day, the President of the Royal Society himself uses the same unit for his bath-water and his water-bath.