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In various months of the years between 1960 and 1972, the R.R.S. “Discovery II” and R.R.S. “Discovery” carried out a number of echo-surveys in the North-eastern Atlantic Ocean between Latitudes 12° and 62°N, and from the European and African coasts to a longitude of approximately 29°W. The prime objective was to acquire data on sea-floor topography. In addition, numerous echo-traces of biological scattering present in midwater between depths of approximately 35 and 460 m were obtained. The traces were of variable quality, but were considered suitable for a preliminary evaluation of the scattering mainly as a basis for further investigation. The scattering recorded in daytime was broadly divisible into three types: (1) Diffuse layers, which were probably due to dispersed single fish. These were not analysed further. (2) Very small discrete echoes, mostly derived from single fish and very small shoals. These were mapped to show geographical regions of greater abundance. (3) Larger discrete echoes, most of which were almost certainly given by fish shoals. These were analysed in detail and information obtained on depth distribution, shoal density, geographical distribution and relative abundance. Small and moderate-sized shoals were found to be very numerous in spring and summer in oceanic water to the West and North-west of the British Isles. Large numbers of shoals of various sizes were also observed at various time of the year in the Bay of Biscay and near certain parts of the European and African Continental Shelf, near certain seamounts, and near islands such as the Azores, Madeira, and the Cape Verde Islands. In general, shoals appeared to be relatively sparse in the more southerly temperate and subtropical regions of the open ocean. The depth distribution of shoals in open water varied greatly but, on average, the maximum daytime depth of those in the more southerly area of the survey was slightly greater than that of those in the more northerly area. Shoal size also varied, shoals to the north of Latitude 50°N were on average slightly smaller than those detected in southerly regins. Possible identification of the fish is discussed.

Measurements of the intensity of diffracted X-rays are usually expressed as a fraction of the intensity of the incident beam. Such measurements become difficult when fluctuations of the mains voltage and frequency cause variations in the intensity of the incident X-ray beam. This problem is solved by the use of the present monitor in which the incident X-rays produce ionization in a short length of their normal path and the ions so produced are used to measure the intensity of the X-rays at the same time as they are being diffracted. The ionization current operates a Wheatstone bridge circuit and the indicating galvanometer operates a photocell system so that the steady rate of movement of the galvanometer is recorded. This is taken as the measure of the incident X-ray intensity and the accuracy of the measurement is about 1%.

Thermodynamical considerations on the vapor‐phase growth of whisker and platelet crystals of α‐Al2O3 by the oxidation of aluminum lead to the conclusion that the vapor‐phase mass transport is probably due to the suboxide Al2O and not AlO as previously suggested. Electron microscope observations confirm the optical evidence that spiral growth steps do not occur on the (0001) surfaces of Al2O3 crystals grown in this way.

When the IIOE was planned, it was considered a valuable objective to examine the upwelling regions which had been reported in the Arabian Sea (Bobzin, 1922) but had never before been the object of scientific observation.