THE fourth report of the North Sea Fisheries Investigation Committee contains a number of papers on hydrographical researches in the northern part of the North Sea and the Færöe-Shetland channel which are of specia interest, inasmuch as they provide a résumé of the work done since the committee began its labours, and a statement of certain results and conclusions which may now be accepted as definitely established and used as standards for comparison with future observations. These papers are:— (1) and (6) on hydrographical investigations in the North Sea and Færöe-Shetland channel during the years 1906–7–8 by Dr. A. J. Robertson; (2) on the temperature of the surface waters of the North Sea during the years 1906 and 1907, by Mr. Frank G. Young; (3) on the salinity ol the North Sea, and (4) on surface-temperature observations between Hull and Hamburg during the years 1877–83, by Prof. D'Arcy Thompson; and (5) on the deep currents of the North Sea as ascertained by experiments with drift bottles, by Captain C. H. Brown. Dr. Robertson discusses the observations made during the periodic cruises executed by the SS. Goldseeker on lines laid down by the International Council. Mr. Young subjects to harmonic analysis temperature observations made by captains of passenger steamers and officers in charge of certain lightships and lighthouses. Prof. D'Arcy Thompson reviews in his first paper a long record of surface-temperature observations made between Hull and Hamburg by Captain W. Barron, and examines the relation of the sea temperature in the southern part of the North Sea to the air temperature of the adjacent coasts, and in his second paper gives an account of the mean values of salinity in the waters of the North Sea—the general distribution of salinity, its mean periodic variation, and the epochs of maximal and minimal salinity. Captain Brown reports upon experiments with the drift bottle devised by Mr. G. P. Bidder, which is so constructed as to float a few inches above the sea bottom, being carried along by the bottom current, and in the course of time scooped up by a trawl-net or found stranded on a beach.