Members will have learned with regret of the death of Dr. L. J. Comrie, M.A., PH.D., F.R.S., who died at the age of 57 on 11 December 1950. Dr. Comrie's contributions to science were primarily in the fields of astronomy and computation, and in the latter field he may be said to have created the modern concept of scientific computing and to have laid the foundations for the present widespread interest in numerical methods and in digital calculating machines. Tributes to this side of his work have already been paid, both here and abroad, and the Royal Society and the Royal Astronomical Society are both publishing fuller notices which will give a detailed assessment of his work. The following note, pays a tribute to Dr. Comrie's contribution to navigation.