The increment of displacement produced in 1000 grams of water at 19·5° C, when 1/2 gram-molecule of potassium chloride is dissolved in it, is 14·001 GT; when a molecularly equivalent amount of potassium bromide is dissolved in the same quantity of water, the increase in the displacement is 17·547GT; when the salt in solution is potassium iodide, the number is 22·778 GT. Replacing, therefore, the chlorine by bromine increases the displacement by 3·546 GT; and if the bromine be now replaced by iodine, there is a further increase of 5·231 GT in the displacement; or, replacing the chlorine by iodine causes an increment of displacement of 8·777 GT.