The shells of certain molluscs which are obtainable on the seashore between tides are seen to be more or less coloured green. I have noticed a fine rich colour on the operculum of a Turbo from the Pacific Ocean, which had been killed and the shell preserved dry. The shell has a high polish, the colour is the rich green of an ivy leaf, and the pigment is contained in the shell material. When the mollusc dies, and the shell is left exposed to air, light, and water, the green becomes a brownish-yellow colour. Some specimens of spirit, which had been poured off shells and fragments of coral obtained by dredging in deep waters, were examined by me for Mr J. T. Buchanan.

In January I read a paper on the salinity of the Firth of Forth, in which the law governing the distribution of salt in that estuary was pointed out. It appeared that in the eastern or seaward part of the Firth the change in mean salinity per mile was very slight, and the tidal range was small, while both decreased gradually as the sea was approached. On the other hand, the riverward half of the Firth showed a rapid alteration in density along its length, and a correspondingly great range between high and low tide.

In the case of a metallic conductor the resistance may be got at once by means of Ohm's Law. But when the conductor, the resistance of which is to be determined, is an electrolyte, the electromotive force acting along the circuit is only partly employed in producing the current.

“Go to the quality of the active principle; abstract it from the material, and contemplate it by itself. Then determine the time; how long, at furthest, this thing, of this particular quality, can naturally subsist.”—Marc. Aurel., Book ix. sect. 25.

In the course of the autumn of this year (1885) I have taken several occasions to determine the distribution of temperature in the water of Loch Lomond. The results of these observations are interesting, as indicating the march of temperature in the different layers at different localities in the lake, and also the gain and loss of heat with the changing seasons.

I will commence my paper with a brief description of the typical characters of a reef in this region, referring particularly to the distribution of the corals. There would appear to be a large number of new specific forms among the reef-corals of these islands, whether hydroid or actinoid. Out of nearly seventy species that I sent to the British Museum, almost a quarter are new or undescribed; and there is every probability that similar success will fall to the lot of other collectors in these seas. There is yet much to be learned of the fauna of the deeper parts of the reef-coral zone; and patient dredging will doubtless yield fruitful results. Here, not improbably, will be found the corals of deep-sea genera and the Rhynconella that I discovered in an upraised barrier-reef in the Shortland Islands. Having only a small canoe, I was not able to dredge in these depths; but I may remark, as a good omen for others, that, when sounding off a reef on one occasion, I brought up from a depth of 14 fathoms a new and very distinct species of Distichopora (D. ochracea), which is described and figured by Mr J. J. Quelch in the Annals and Magazine of Natural History for July 1885.

An occurrence of an extraordinary nature took place in the kitchen of this house on Monday evening, the 8th inst. The kitchen is in the area, and whilst the office-keeper and his wife and servant girl were seated in front of the fire, suddenly, about twenty minutes past eight, a terrific rumbling sound was heard in the chimney. Fearing that something was about to topple about their ears, they all sprang aside, and no sooner had they done so than a large sheet of flame issued from the chimney, and without disturbing the ashes in the grate, or touching the grate itself, swept close past the office-keeper, who was standing nearest to the fire-place, and extinguished the gas.

This paper contained an account of the experimental evidence in support of the theory of solution enunciated in a paper “On the Nature of Solution,” communicated to the Society in January 1883. Solution of a salt in a liquid is a consequence of the attraction of the molecules of the liquid, for a molecule of the salt (adhesion), exceeding the attraction of the molecules of salt for one another (cohesion). As the number of dissolved salt molecules increases, the attraction of the molecules of liquid for the molecules of salt becomes more and more balanced by the mutual attraction of the salt molecules. When these two forces are in equilibrium, saturation ensues.

During the spring of 1882 Mr Burton and I communicated some preliminary experiments on a new method of measuring the heats of combination of the metals with the halogens.