The electrical resistance manifested relatively by certain fused salts is peculiar. The following communication contains the result of observations on time changes of resistances noticed during the cooling and resolidification of two typical groups of fused salts and also of molten glass.

When the compressibility of a liquid or gas is measured at very high pressures, the compression vessel has to be enclosed in a strong cylinder of metal, and thus it must be made, in some way, selfregistering. I first used indices, prevented from slipping by means of hairs. Sir W. Thomson's devices for sounding, at small depths, by the compression of air, in which he used various physical and chemical processes for recording purposes, led me to devise and employ a thin silver film which was washed off by a column of mercury. Much of my work connected with the Challenger Thermometers was done by the help of this process. Till quite recently I was unaware that it had been devised and employed by Cailletet in 1873, only that his films were of gold.

The question as to the normal duration of the life of red blood corpuscles has hitherto been considered more as a matter for speculative inquiry than for experimental proof. Attempts have from time to time been made by various observers to solve it experimentally, by injecting the blood of one animal into the circulation of another, whose blood corpuscles were of different size and shape, and then noting how long the foreign blood corpuscles remained discoverable in the body of their host. As might have been anticipated, the success of such experiments has not been very striking.

A short time ago I published a method in the Chem. News, vol. liii. p. 41, “On the use of Hydrogen Peroxide as an oxidising agent for detecting and estimating Manganese;” showing the advantages it had over other sources of oxygen for oxidation purposes, simply on account of the fact, that when using hydroxyl you do not introduce any objectionable foreign substance, such as manganese, chromium, potassium, lead, &c.

The author has recently been engaged in a variety of electrical observations in connection with wrought iron and steels, in the course of which it occurred to him to investigate some of the effects produced in the presence of nascent oxygen, of the ozone type, by a current of sufficient strength to readily decompose these metals by oxidation whilst immersed as electrodes in distilled water, the great resistance of the latter apparently facilitating the interesting results observed and recorded below.

The foregoing paper was read on 5th July 1880. We postponed, however, its publication, feeling that however interesting the formation of the bodies therein described might be, much careful quanti tative research would have to be undertaken before any definite conclusion as to the true nature of these bodies could justifiably be drawn. Only the title of our paper was therefore published in the Proceeding of this Society. The old University Laboratory being in many respects'unfitted for the prosecution of accurate quantitative work, our researches were repeatedly postponed in the hope of being able to continue them in the new University Laboratory, which, however, only now approaches completion. This delay has been to us a subject of much regret, the questions involved being of no little interest.

The temperature of water can be ascertained much more easily than that of air, and with far greater accuracy; yet comparatively little has been done by meteorologists in the way of obtaining data bearing on the distribution of temperature in rivers and in estuaries. Some observations of great value have been discussed by Mr Buchan in the Scottish Meteorological Society's Journal, but these were discontinued after a few years.

Telegraphic communication between-Ben Nevis Observatory and Fort-William Post Office is kept up by means of a line which consists of an ordinary telegraph wire from Fort-William to Auchintee Farm at the base of the mountain, and a cable laid underground from thence to the summit. At Fort-William the wire is put to earth in the usual way, while at the Observatory the return wire is attached to the iron-wire sheath of the cable.

The following results of observations made with four of the thermometer screens, devised by Mr Aitken of Darroch, form the commencement of an investigation which has been begun at Granton Marine Station, and which is to be carried on there and at Ben Nevis Observatory during the summer and autumn, with the view of finding a more suitable screen for exposing thermometers for meteorological purposes, and, if possible, of determining the mean correction to be applied to the readings of thermometers exposed in the ordinary Stevenson screens. So far, the work has been entirely of a preliminary character, but some points have been brought to light which are of considerable interest.

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.

As the result of Andrews' experiments on the boiling-points of substances, we have the law enunciated that There is a critical temperature for every vaporous or gaseous substance ; such that, only when its temperature is below this, can the substance be reduced to the liquid form by any pressure, however great. Similarly, a law may be laid down regarding the passage from the liquid to the solid state, or vìce versâ. Thus we may say that There is a critical temperature for every solid substance, which contracts in the act of liquefaction, such that only when its temperature is above this, can the substance be reduced to the liquid form by any pressure, however great; and for every liquid substance, which contracts in the act of solidification, such that only when its temperature is below this, can the substance be reduced to the solid form by any pressure, however great.