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"The air motion in cyclones is one of indraught, and therefore the wind direction at any point is not at right angles to the direction of the centre. The stream lines, or the lines of air motion, are spiral curves. The relation between the wind direction and the direction of the centre is probably not invariable, but depends upon the intensity of the storm or the baric gradient. The law laid down by Mr. Willson in the Report on the Midnapore cyclone is probably the nearest approximation. It is with the face to the wind, the direction of the centre is from ten to eleven points to the right-hand side.'

It is, therefore, evident that meteorologists must look to the physicists and mathematicians for a more complete explanation of the genesis of storms than they at present possess, before they can feel at all certain of the conditions under which they arise. Mr. Eliot, in the Report which has just been quoted, devotes an immense amount of attention to the origin of the cyclone he is describing, which he attributes to a heavy and persistent rainfall: "the immediate antecedent is heavy rainfall concentrated over a portion of the bay, accompanied by strong indraught, &c., &c." He, however, is unable to tell us what has produced the rainfall : what has set the ball rolling. Mr. Eliot fairly enough criticizes other theories, but he lays himself open to the same charge which he brings against others: he has not fully demonstrated the ultimate principle underlying the whole phenomenon.

When we have thus seen how little we really know of the phenomena manifested in the air about us, it is only fair, by way of justification for the shortcomings of our science, to point out some of the reasons for our helplessness.

In the first instance, we are dependent for our information as to the actual weather which is prevailing about us, on reports from a number of stations distributed over the country; but we cannot afford, on the ground of cost, to receive information frequently enough, or from a sufficiency of stations; while the information itself is not sufficient in quality. These observations are necessarily taken by landsmen, who are shut up in offices or houses for several hours in the day, and are quite debarred from e constant opportunity of watching the weather and its changes

which is enjoyed by the seaman at sea. In short, the reports which we receive are not such as we should expect to get could we learn from an experienced captain off the coast the description he would give of the look of the clouds and sky. Moreover, even if the reports were full and accurate enough when framed, it would be impracticable to telegraph them. It is, therefore, clear that meteorologists suffer from deficiency of information.

There is, however, one all-important obstacle in the way of our gaining a knowledge of the condition of the atmosphere as a whole. We know literally nothing of the phenomena taking place above our heads; the stratum of air with which we are dealing, in the way of gauging its condition and its motions, is infinitesimally small as compared with the heights of the atmosphere itself.

There is not a station in existence where observations are regularly taken 100 feet above the level of the ground, and if we come to elevation above sea level, the mountain stations are few and far between, and the highest of them all, Pike's Peak, in the Rocky Mountains, only attains the level of about 14,000 feet. Observations have certainly been made at various heights in balloons, but these efforts are necessarily spasmodic, and simply furnish facts to serve as a basis for theories of the general condition of the upper air. They certainly can never be expected to afford us constant intelligence of the phenomena of weather prevailing over our heads.

It is our ignorance of the amount of moisture in the higher strata which prevents us from forecasting quantitatively the amount of rain which is likely to fall. We may, and do, know when thunderstorms are likely to occur, but we cannot say beforehand whether the rain that they bring us will measure a quarter of an inch or ten times as much. That knowledge of the condition of the air even 9,000 feet above us would be of great value, is shown by the fact that on one occasion, a few years ago, General Nausonty, on the Pic du Midi, knew, by the setting in of a warm wind with rain, at his high station, that floods must ensue in the valleys below, and had he possessed telegraphic connexion, he might have issued warnings fully two days before the calamity occurred.

The fact is, that considering the manifold deficiency of the data on which we have to base our predictions, it is a comfort to know that we can score any success at all for them, and that we do score a fair amount, the testimony of our coasting population is amply sufficient to show.

There is, however, one remark which ought to be made with reference to the prediction of weather. We hear the opinion very commonly expressed that the barometer is of no use now-a-days; that on such and such an occasion rain came with a rising or dry weather with a falling glass; or captains tell us that in their experience the barometer is of no service near Cape Horn, where its usual height is more than half an inch below the level to which we are accustomed in corresponding latitudes in the Atlantic.

All such remarks simply show us that the schoolmaster is abroad, and that people are paying more attention to their instrumental readings and to the weather in general than they did twenty years ago. A single barometer will not enable us to form an accurate judgment of coming weather; firstly, because the weather, as far as the barometer is concerned, depends not on the actual reading at any one place, as would appear from the words "fair,' 99 66 change," &c., on old barometer scales, but upon the simultaneous changes going on over the surrounding country; and secondly, because readings of the barometer must be combined with careful observations of the changes which have taken place in the thermometer and hygrometer, in the direction and force of the wind, and above all in the character, height, and motion of the clouds.

The last-named observations are the most important of all, but they are by far the most difficult to make, as the faculty of forming a correct opinion on them at once places its possessor on a very high level indeed as regards the valuable power of predicting local weather.

In conclusion, we must only say that though accurate prognostication of coming weather is at present impossible, the solitary observer need not utterly despair. Buys Ballot's law of the relation of wind to barometric pressure shows us that the direction of the wind always indicates roughly the bearing of the region of lowest pressure in

the neighbourhood of a station, and the rise or fall of the barometer itself, taken in conjunction with the changes of the wind, gives very useful information as to the motion of the system of low pressure, whether it is approaching to or receding from the station. In fact a careful observer of barometer and wind may form a good idea of the weather immediately coming, especially if he is a good judge of clouds and weather.

The power of a single observer is the mainstay of our seamen's weather knowledge, for they are necessarily isolated, and to that power we must cling till our scientific men give us something better.

LOSSES OF GRAIN SHIPS.

UR pages, like the columns of our excellent contemporary, The Shipping and Mercantile Gazette, have for some months contained letters and articles on the subject of the dangers of cargoes of coal and grain arising from their stowage, and some very pertinent remarks and suggestions have been thrown out concerning the causes of the great losses which have recently happened. The letters on the subject have been almost exhaustive, and many of them have been marked by an unusual amount of ability and completeness. The conclusion to be drawn from the discussion, letters, and notices down to this time is, that if grain is carried in bulk, it ought to be only so carried in ships which, owing to their form and construction, can carry it in safety.

If a ship is deep in proportion to her length and breadth, and if she is loaded with a bulk cargo in such a way as to give her a very small freeboard, and at the same time to give her little or no stability, it is not surprising that she should manifest an inclination to roll. She is very much like a barrel, so far filled with water as just to enable it, when thrown into the sea, to present a small part of the surface of its circumference above the water. If at the same time no weight is attached to any part of the circumference of the barrel to keep that part downwards, the

barrel will certainly roll over and over. If instead of placing a weight on a part of the circumference, a bladder of air is attached, the barrel will then assume a position in which the air bladder will be on the surface of the water. Given, therefore, a ship deep in proportion to her breadth, with air spaces at the bottom, and the hull so filled up that the vessel has little or no stability when upright, and is at the same time very low in the water, and further given the fact that she is turned on one side by the wind or sea, and that the cargo moves over towards that side, is it surprising that the ship acts as the barrel would act, and turns her air bladders (ballast tanks) upwards. Yet this simple experiment or demonstration goes on at intervals, and every one wonders. They do not, however, wonder that the experiment or demonstration should invariably come out as it does, but they profess to wonder that another well-found, seaworthy, highly-classed ship (and her crew) should disappear! If in addition to the exceedingly favourable provisions and conditions provided for rotating a ship on her longitudinal axis, to which we have already referred, the circumstance that there may also be a lodgment space on deck, for from 60 to 150 tons of water, and that there may often perhaps be greater facilities for this water finding its way down into the ship than over the side, the matter seems to be fraught with still more wonder. It is possible that Mr. Plimsoll's disc is sometimes one of the agents in securing danger. We have, for instance, noticed that in some ships a solid plate is carried a foot (more or less) above the side at the deck planking, near the water-way; that it has a moulding round its upper side, and the openings for relieving the deck of water are above it. This may give a fine appearance of freeboard, but it is questionable as regards safety, especially when solid iron bulwarks with but few openings are above it.

Our contemporary, The Shipping and Mercantile Gazette, informs us that an "understanding" has been "arrived at with the Board of Trade, by the Associated Chambers of Commerce, and the Chamber of Shipping, that in future no prosecution should be instituted against masters or owners under the Act of 1876 with reference to the shipping of grain cargoes stowed in bulk, where it

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