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APPARENT AND TRUE DIRECTION OF THE WIND WHEN SAILING. 299

Now, the sum of the two sides of a triangle is to their difference, as the tangent of half the sum of their opposite angles is to the tangent of half their difference.

V+ R the sum of the angles opposite to v and r must be the apparent direction of the wind to the course reckoned from aft; and hence, generally,

R);

v + r : v − r : : tan ¦ (V + R) : tan † (V knowing (V+ R), and having determined (VR), the sum of the half sum and half difference gives the angle V, as the true direction of the wind to the course; and the difference of the half sum and half difference gives R the divergence of the apparent and true winds, that is the angle by which the apparent is more forward than the true wind. This is when the wind velocity is greater than the ship's rate; should it be otherwise, we have

V)

r + v : r = v ; : tan † (R + V) : tan † (R On the basis of these formulæ the annexed table has been computed.

The true velocity of the wind may also be ascertained, since the sides of a triangle are to one another as the sines of the opposite angles; hence,

tv

sin T: sin V; or tr:: sin T: sin R in which the angle T (opposite to t) is known, since V and R are known; and the solution gives t, the wind's true velocity.

On constructing a figure, or referring to the Table, it will be seen that

1. When the true direction and velocity of the wind remain unchanged, and the ship's course is also unchanged, then the apparent direction of the wind will vary as the ship sails faster or slower. The divergence of the apparent from the true direction increases as the ship's rate increases, and decreases as the rate decreases.

2. When the ship maintains the same rate under winds of different velocities, but inclined at the same angle to the course, the divergence of the apparent from the true direction of the wind will be greater as the wind is slower, and less as it is faster. The Table sufficiently explains itself.

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The TRUE DIRECTION of the WIND to the Course is

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GRAIN AND COAL CARGOES.

"EX LUCE LUCELLUM."

Was it guile, or a dream?

Do I wonder and doubt ?

Are things what they seem?

Or is visions about?

Is our civilisation a failure?

Or is the Caucasian played out?-BRET HARTE.

HE recent losses of new, or comparatively new, iron steamships, laden with coal or grain, has called very

serious attention to many facts connected with their

proportions, construction, fitting, and loading. But the most startling fact of all in connection with the subject is that the great majority of them were new steamships of a special class, built under a special rule, and classed as 100 A1; that is to say, they go over the seas (or rather did go until they disappeared) bearing the imprimatur of the highest and best classification society in existence, as evidence that they were fit to carry any and every description of perishable cargo from and to all parts of the world. The fact that so great a number have disappeared, after being so guaranteed, may, we think, be legitimately called a startling fact. The majority of these ships possessed in common certain marked characteristics, viz., narrowness, depth, length, water-ballast tanks or double bottoms, square midship sections, low freeboards, two decks and three tiers of beams, small crews, bulk cargoes. The reason why they had bulk cargoes is plain; the reason why they had comparatively small crews is plain; but the reason why so many of them should have possessed the other characteristics to which we have referred is not at first sight plain. That the majority of them were strong "girders," or strong oblong boxes is evident, and the cause of their disappearance is clearly not to be sought in any element of structural weakness of the hull.

*It may be that coal not being a "perishable" cargo they were not classed to carry coal.-ED. N.M.

In one or two cases the skylight arrangements were perhaps flimsy, and may have helped the loss; but this is not at all a common characteristic running through the series. Just as some years ago there was a class called "awning-deck" steamers, now, we think, going out of use; so at the present moment there is a fashionable type of steamships in which the register societies have enumerated the majority of those recently missing with bulk cargoes. Looking round with a view to finding some cause for the present fashion, it is possible that it may be found in the encouragement given to the development of depth over other proportions by the special Rule 41 and Table G of the Committee of Lloyd's Register. In the same way and to the same extent that a set of ships, including many which were exceedingly dangerous when laden down with a full cargo, was called into existence some years ago as awning-decked ships; so now it is abundantly clear that a class of so-called "three-decked" ships, including many exceedingly dangerous, when not loaded with care, has sprung into existence. Ships exceedingly strong as girders, but exceedingly ugly as parallelopipedons; safe enough when properly loaded and with ample clear side, but veritable coffins with four feet or less clear side, when carrying certain cargoes, raised on the platform composed of empty air spaces at the bottom of the ship.

"Alter

How has this state of things, culminating in these dangers, come about, and how is it to be remedied? To these pertinent questions Mr. Benjamin Martell, the chief surveyor of Lloyd's Register, has found an answer, to his mind, satisfactory: "It is the fault of the tonnage laws," Mr. Martell assures us. the tonnage laws so as to exempt a good deal more of a steamship from tonnage measurement, and," he comforts us, "the evil is cured." The completeness of this suggestion, as combining at once a statement of the cause of the creation of structures which, when badly loaded, are fraught with danger, and of the cure, is so sweetly innocent and simple that we cannot pass it over, even if we would. First, however, we must place Mr. Martell on our own side as a witness to the alarming magnitude of the danger under ortain known conditions, of certain ships, built under Rule 41 and

Table G. In making our remarks, we wish to be understood that we can find no fault with those who administer the classification rules; those officers are as desirous as any of us to contribute to the safety of life and property, and it is towards an amendment of the rules, rather than a censure on their administration, that our remarks, so far as they apply to those rules, are directed.

Mr. Martell testifies as follows:

"The demand for cargo steamers during the last year or two for the trying Atlantic trade, and the generally-depressed condition of other trades, have caused many owners to send vessels across the Atlantic in mid-winter who doubtless would otherwise scarcely have thought such vessels suitable."

"As the steam-carrying trade became developed, and steamers became built for longer voyages in the Baltic and Mediterranean, greater length was given than in the earlier vessels, while all the objectionable features of extreme fulness of form and flatness of floor were retained. Two principal causes doubtless operated to retain these features in cargo steamers."

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"In the first place it was thought, the less the area of midshipsection to drive through the water under the same displacement, the less the propelling power required. And secondly, that as steamers differed so widely from sailing ships in having no topweight of heavy masts, and their stability consequently, when light, was so much greater, that there was less necessity to have a rise of floor to insure sufficient stability in shifting when discharged. Consequently the two great advantages were obtained in having a flat floor, riz.: the reducing the draft of water with the same displacement, and the carrying the greatest cargo under the same principal dimensions, whilst being able to place the engines and boilers as low as possible. The result of this has been to destroy nearly all beauty of architectural form in a large proportion of seagoing cargo steamers, by producing an approximation to a rectangular prism, whilst at the same time, as will be shown, it has at last been the means of introducing a positively dangerous element in this class of vessel."

Coming now finally to the vessel of the same length, 245 feet, and whose scantlings are continued of the full size to the upper

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