The late Mr. W.W. McNair.--Colonel T. H. Holdich, R.E., sends us from India the following additional details regarding the career of Mr. McNair, briefly noticed in our last issue:--Amongst the many practical geographers who have passed away during the year 1889 is Mr. W. McNair, of the Indian Survey Department. His career was very closely connected with a new phase of military exploration carried out on the frontier of India, which had gradually superseded the older forms of reconnaissance, and was rendered possible by late improvements in the smaller classes of instruments, and a wider knowledge of the use of the plane-table. For about ten years previous to the Afghan War of 1879, McNair was attached to the topographical branch of the Indian Survey, and he had always shown a special aptitude for that class of work, which consists in acquiring a comprehensive grasp of a wide field of geographical detail in the shortest possible space of time. When war broke out, Afghanistan no longer afforded a field for such simple geographical exploration as had already been accomplished during the campaign of 1839-43. A completer military survey of all important districts was required, which would furnish detailed information of routes and passes which were far removed from the beaten tracks of previous armies. At the same time the conditions under which such a survey was to be made were exactly the same as those under which the rough reconnaissances of the former campaign were obtained. The surveyor was under the same urgent restrictions, both as to time and as to the limits of his own movements off the direct line of march. McNair, with one or two others, was selected for this topographical duty with the Afghan field force, and right good use he made of his opportunities. He was present during the fighting which took place before Kabul in the winter of 1879-80, and was shut up with the garrison of Sherpur during the fortnight's siege. His energy and determination carried him through the campaign with more than credit--he was able to illustrate modern methods of field topography in a manner which threw new light on what was then but a tentative and undeveloped system. He was one of the first to prove the full value of the plane-table in such work as this, for it must be remembered that he was working in a country peculiarly favourable to the application of a system of graphic triangulation, and very different to the densely forest-clad mountains of the eastern frontier into which the plane-table had been carried before, with advancing brigades. At the close of the war, which brought no recognition of his exceptional services, he was appointed to the Kohát survey party, which was primarily raised for the mapping of the Kohát district, but which afforded occasional opportunities for extending topography across the border. When this party was first raised our frontier maps were of the most elementary character; there was many a wide blank in the