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2. " The contractile force of the muscles in a healthy man, according to Dr. Young, is equivalent to about 500 pounds for each square inch of surface presented by their transverse sections. We may then easily understand why it is that the most powerful men have their muscles most developed, and why the largest muscles are placed in those parts of the body where they are subjected to the greatest quantity of work."
The remarkable stout thighs of seamen must strike the most careless observer. This arises from their constant practice of exercising the muscles in the action of going aloft, and whilst upon the yards, by which they become more developed, and their power increased to a much greater degree than in men of other laborious pursuits, who do not employ the legs in ascent and descent. The muscles of the arras in the same class, from constant exercise, are also much enlarged, and their strength increased. Seamen in sound health are, probably, the strongest of men with respect to muscular power, and the reason why they should be seems sufficiently obvious.
3. " It is well known that the quantity of labour which the muscles will endure, and the length of lime they will continue to act, increase, within certain limits, in proportion to their daily exercise."
Experience proves the above assertion. The practice, however, in the Merchant Service, of "getting the worth out of a seaman," as the phrase is, may be carried too far, and prove detrimental to his health, if it should not ultimately lead to loss of life, especially in tropical climates.
The habit, too, of supplying the seamen with drams whilst employed on some active duty which requires extra, or continued exertion, for the purpose of increasing their energy, by imparting an artificial strength to the muscles, is highly detrimental to health. The effect desired, it is true, may be produced, but it will be but temporary, (which perhaps, is all the employer cares for!) and seldom fails of creating re-action, which acts upon the whole nervous system. This practice appears to be more pernicious in cold than in tropical climates, probably on account of evaporation, &c, being stronger in the latter than in the former; but it should be discontinued altogether. From actual experiment it has been found that, if two large bodies of men, engaged in the same laborious work, the one being supplied with spirits, and the other with a strong coffee beverage,—the former lost the 'power of exertion some hours (if I remember right, five,) before the latter, who continued to work on with apparent ease.
4. " If the muscles of the arms and legs, or any others, be called suddenly into action for a longer period than that to which they have been accustomed, they soon communicate to the individual a sense of weakness, and evince a disposition to yield to the action opposed to them, and unless they are allowed some repose, mischief speedily succeeds."
This is a plain matter-of fact exposition of an every day occurrencei over-exertion; but, which, when circumstances press, and authority directs, is not always attended to, or averted by timely relief from fatigue; indeed, parsimony, and the utter want of that christian feeling, the precept of which is admired, but often neglected in practice,— "Do unlo others as you would be done by;" often, nay, generally, is the cause of such occurrences. Let the ship-owners ponder on the consequences that may, and do often occur from their ships being undermanned. Let them consider for a moment the dreadful situation of one of these short-handed ships after having weathered a furious hurricane, springing a leak! Let them fancy the small band of stout hearts being obliged to take spell and spell at the pumps; the leak as the muscular power of the devoted men declines, increasing rapidly, and preventing the possibility of a thrumbed sail being passed over the bows, until at last, wearied to exhaustion they drop as the vessel sinks under them! Let them think seriously of such a result arising from the economy of sailing a ship at the least possible expense, regardless of the souls within her—and, apply a remedy.
5. " But there is a limit to the amount of exertion which the muscular system will bear; if this limit is passed, the muscles lose their vigour, and lassitude and a flaccid state supervene."
This is inevitable, and addressing myself to the captains of ships, I beg to remark that, when a weighty cargo is to be hoisted in, and stowed away by the crew, the performance of which would necessarily require the whole power of the muscles to be exercised, the sooner the labour is commenced after daylight the better, and it would be advantageous to all parties to lengthen the period allowed for meals by at least half an hour; and to leave off work half an hour, or even an hour sooner than on ordinary occasions. More work would be performed, and what is of equal importance performed well. The material point for the judgment to aim at, in laborious duty, being to avoid over-working the muscles, by which the change from a healthy tone or tension to one of flaccid ity is prevented.
6. " I have before stated that the weight of the body is proportioned to the cube, and the power of the muscles to the square, of some one of its dimensions: for instance, in two similar-formed men, whose heights are respectively five and six feet, the muscular power of the former to that of the latter will be as 25 to 36, but their weights will be as 125 to 216, or, as 25 to 43 very nearly; the weight, therefore, increases much more rapidly than the muscular power, and, consequently, a smaller man is stronger, in proportion to his size, than a larger one." And, I may add that, he will do more general work, and endure more fatigue, and that for a longer time than the larger man. In our men-of-war activity is much prized, hence in the selection of top-men this point is always attended to.* If, therefore, the shipowner and captain, would leave prejudice, which is founded on error, aside, and, the former not allow his spirit of economy to interfere with the efficiency of his vessel, ships would be navigated with more ease and safety than they are at present.
There is a curious phenomenon exhibited in the paper from which these extracts have been taken, respecting the predisposition to corpulency from the neglect of the proper means of checking it; but I pass
• What the object was for weighing lads I do not know, but if it was from an opinion that weight implied strength, the above will show that it was likely to prove erroneous!
it by, as there is little fear of a seaman becoming plethoric, or adipous, whilst serving in a merchant-ship; the owner and the skipper taking especial care to prevent such from arising from good or over-feeding, or from lack of exercise!
Muscle versus Weight.
Wrecks Of British Shipping.
(Continued from p. 200,—cs, crew saved; ed? crew drowned.)
For reducing Chinese Changs to English Fathoms, and English Fathoms to Chinese Changs.
An Ancient Anchor.
The old anchor of which the annexed is a sketch was trolled up in a net in the month of July last year, about three miles from land, opposite to a place called Burmiston, in nineteen fathoms water; Scarbro' castle bearing by compass S.W.b.W.
Sir.—Referring to a point touched on in the paper on the " Merchaiit Service," the wool cargo, I beg to make a few observations.
Can any other conclusion be drawn from the fact of the steam arising from the cargo being allowed to pass through the seamen's berth, than that, such has been permitted, because it was the most economical plan; a plan, which although it may save a few pounds to the owner, jeopardizes the health and lives of the crew!
The remedy appears to be easy. Wooden flues would carry off the steam into the atmospheric air, and prevent it from affecting any person on board the vessel. Why have these not been erected?
It is deplorable to think how little care is bestowed upon the state of the seamen's berth on board of merchant ships. In the Australian traders the bulk-head between the hold and the men's berth is purposely left with interstices to admit the steam and fume from the wool cargo to pass through I The effect has been described, and I have been assured that when a person holds his head over the scuttle, the steam condenses on his face and runs off in drops 1 If the Captain is appealed to by the suffering crew, his answer is, that he cannot permit the bulkhead to be closed, as, in that case, the steam would find vent aft, and annoy his passengers! Without imputing direct blame to the Commander, we may assert it to have been his duty before quitting the home port, to have pointed out to the owner the result that would follow from the general plan adopted, and lo have urged the necessity for a