The following method of sticking hot charcoal powder to cold bodies is given by G. Tammann in Ann. d. Physic: On dipping a cold glass rod into hot powdered charcoal containing very little occluded gas, it is found, on withdrawing the rod, that a layer of the powder sticks to the rod, the thickness of the layer increasing with the difference of temperature between the powder and the glass. If the rod remains long enough in the powder to acquire its temperature the phenomenon does not take place, and, on the other hand, if the rod with the powder on it is held until the powder cools, it ceases to adhere. The other forms of carbon do not exhibit the phenomenon, which, however, is independent of the nature of the rod. With Si02 powder a slight amount sticks, but this does not fall off on cooling. The author shows by using a glass rod in one experiment and an earthed conductor in another, that the phenomenon is not of an electrical nature, no difference being observed in the two cases; also by performing the experiment in air at 0.5 millimeter pressure and finding no change, he shows that the cause is not to be found in the currents due. to occluded gases. He therefore concludes that the attraction is due to a particular kind of field of force only existing with considerable temperature gradient. Two out of the three types of rays emitted by the radio-active elements, known as the beta- and gamma-rays, are substantially of the same nature as those emitted by a Crookes tube. Thus the beta-ray is the familiar electron in motion and corresponds with the cathode-ray, while the gamma-rays result from the beta-rays in much the same way as the X-rays result from the cathode-rays. The difference is that the X-ray bulb acts under the action of a constant supply of external energy and ceases to work the moment the supply fails, whereas the radio-elements are entirely independent of external stimulus or supplies of energy. In the resemblance between the beta-rays and gamma-rays and the cathode-rays and X-rays of the Crookes tube there is an important difference. The electron which constitutes the cathode-ray travels ordinarily at a speed about one-tenth that of light, whereas the beta-rays of uranium travel with a speed about seven times greater. Like the cathode-rays, the beta-rays are deviated by a magnet, but with much greater difficulty. Some of the beta-rays of radium have a velocity 95 per cent that of light. The beta-rays are not penetrating enough, while the gamma-rays are too penetrating for radiography. Eight centimeters thickness of aluminium are necessary to absorb half the gamma-rays, while Rutherford has shown the effect on an electroscope of the gamma-rays from 30 milligrammes of radium bromide after passing through a foot thickness of iron. All three radium emanations possess the extraordinary power of imparting to inactive solid objects in the neighborhood a new and distinct type of temporary activity. This imparted activity decays also according to regular laws, which are characteristic and distinctive in each case for the different elements from which they are derived. This process has been elucidated and shown to be due to a change occurring in the gaseous emanation. Gradually and continuously it turns into a new type of radio-active matter, non-volatile and so depositing itself as a film upon any solid object available. The films are invisible and unweigh-able, and are only known by their activity. Nevertheless, if such a surface rendered active by exposure to the emanation is scrubbed with sand-paper, the film is removed and the activity is then found on the sandpaper. In consequence mainly of these and allied phenomena the view was put forward in 1902 by Prof. Rutherford and Prof. Soddy that the radio-elements were in a state of continuous and spontaneous change, capable of an exact quantitative expression, and that the emanations and allied bodies were the products of these changes. mouth, Devonport, and Dover respectively, while the remaining three bases will be distributed. along the eastern shores on the North Sea, which is the more exposed to attack from the European continent. Portsmouth, owing to the contiguity of the great naval dockyard, will constitute the principal base; but at the same time each station will be so appOinted that it will be in a position to be independent of the paramount base, and be able to cope with any emergencies that may arise, such as the refitting, repair after accidents, and replenishing of supplies. At Portsmouth the base will be quite isolated and independent of the dockyard itself. The situation selected for the station, and upon which the necessary arrangements have been carried to a very advanced stage, is completely isolated by water from all communication with the shore, thereby enabling absolute privacy to be maintained. A small dockyard is being constructed, and is being equipped with all the latest electrical and other power appliances for dealing with the work, together with numerous tanks for storing gasoline. A special type of floating dock is now approaching completion at the works of Vickers, Sons&Maxim, for dealing with submarine craft exclusively. Similar arrangements and facilities are being carried out at Plymouth, the station in this case being also isolated by water, and at the same time guarding the entrance to the important dockyard at Devonport. At Dover, where the naval harbor is being pushed forward with all possible speed, the situation will comprise a floating workshop and dock near the harbor's entrance. This station will prove an important one in the strategical defensive scheme of the Admiralty, since it guards the Straits of Dover, and thus commands the only means of communication between the English Channel and the North Sea. Each base is to be provided with a fast depot ship of sufficient speed, so as to be able to render prompt assistance in the event of a submarine breaking down. This vessel will have a torpedo boat to act as a tender. Owing to the fact that the machinery of a submarine vessel requires frequent overhauling, the exact number of these craft which is to be stationed at each point in actual service, and the extent of the reserves, is not yet finally decided. It is anticipated, however. that each base will be equipped with six active boats, together with a sufficient supply of reserve craft to enable the above minimum number to be available for service at a moment's notice. In view, however, of the satisfaction and success of the latest types of submarines which have been constructed, it has been decided to push ahead with the construction of this class of fighting unit with all possible speed, while the various, bases are to be completed and equipped the present year.