In 1909 I wrote a letter to the GEOLOGICAL MAGAZINE (p. 431) objecting to a statement in a review of the late Sir John Harrison's Goldfields of British Guiana that only products of weathering containing free aluminium hydroxide in hot moist climates should be considered as laterite. This letter led to contributions from the late J. W. Evans, T. Crook, and Sir John Harrison. It is particularly interesting now to read again J. W. Evans's remarks. In the volume for 1910, pp. 189, 190, he said hehad intimate acquaintance with the material to which the name laterite was first given in the area in which it was typically developed. On p. 190 he said that laterite varies, but one feature remains constant, the small amount of combined silica in proportion to the alumina present and that “it is in this respect that laterites differ from clays, which also occur as tropical decomposition products and are sometimes incorrectly described as laterites ”. On p. 381 of the same volume J. W. Evans wrote: “I admit that he (Buchanan) did not know its true chemical composition, but in spite of that it must be accepted as the type of what we ought to call laterite.”