B A L 



its centre mufl remove towards L, fay tor; and, iffromrbe 

 ert-Aed a perpendicular to the horizon, ii will cut the vertical 

 axis at n, which will, in this cafe, be the mctacentrc, above 

 which, if the centr- of gravity were placed, it would act in 

 conjuuftion with trie centre of cavity to ovcrfet the vtfTcl : 

 but, as the centre of gravity is here below it at g, her (labi- 

 lity will be increafed by the increafed diftance of G fiom n, 

 the met:^cc•ntrc ; and the veflcl will roll round the point M 

 as her ceutve of motion. 



Whsn faiii-T; in fmooth water, the greater the (lability 

 the better; but if a vcifel with a heavy cargo, llowed low 

 in her bottom, be fent out into a rough tcinpelluous fea, 

 where evei-y wave will throw her from her equilibrium, (he 

 will return with luch violence as to endanger her malls; and 

 (hould (he be dil'malled, her roll will then be with ftill greater 

 force, pofTibly to the deftruftion of her hull. Was the 

 cargo in this labourfome veflcl to be removed higher up to- 

 wards the centre of motion, fo as to leffen her ftability, (he 

 would be found confiderably eafier ; her roll would be by 

 fuch deliberate motions, as to leffen the danger to her malls 

 and hull. 



The ballall is placed round and very near the centre of 

 gravity of the (hip, becaiife it will prevent the motion of 

 the pitching being lo hard as it would be, if that weight were 

 diflant either afore or abaft that point. Whenever the fea 

 runs a little high, the (hip is never carried by a fingle wave; 

 there are generally two or three always palTuig under at the 

 fame time, unlefs when the fea is extremely long, the fwclls 

 coming from a great diftance, and in latitudes very remote 

 from land; for, then, it happens that the largefl (bips are 

 fometimes carried by one fingle wave. But, in either cir- 

 cumllance, the ballaft ought not to be (Iretched afore or 

 abaft the centre of gravity, as foon as the (hip is in the 

 parallel to her draught of water marked for the ballaft, 

 which it is abfokitely cfTential to pay attention to. To 

 prove this principle, fuppofe in either cafe a long or fliort 

 furge, and that the water ftrikes the (hip forward, that 

 thereby (lie may be expofed to the greateft and hardell 

 pitching; tor when the wave takes a (liip under the ftern, 

 her motions, if fhe has got a little head-way, are not dan- 

 gerous; becaufe, as fhe flics before the wave, flie recedes in 

 fome meafure from its impulfe; while, in the firlt cafe, (he 

 increafes on the contrary that fame impuUe in the ratio of 

 the fquare of all her velocity. 



Firll, the (hip whofe extremities are light or little loaded, 

 being fuppofed to run with any velocity whatever againll 

 the wave which comes to her a-hcad, (hocks that wave with 

 a force exprc(red by the fquare of the fum of the two ve- 

 locities; (he divides it and goes thniugh it, at the fame in- 

 ftant that (he is railed by the vertical impulfe of that column 

 of water, which oppofes to her a fupporting power toocon- 

 fiderable for her weight to difplace; the wave which follows 

 produces the fame effect in receiving the fall of the fliip, 

 becaufe the firft is already under the middle of the (hip, 

 whence it paffes to the ftern, which isfupportcd by it, while 

 the fecond takes its place in the middle, and the third is 

 come to fupport the head; and this is an uninterrupted fuc- 

 ceiTion. This motion continuing thus as long as the fea is 

 agitated, it follows that the (hip is never at retl ; no fooner 

 has (he been raifcd by a wave, but (he falls again when that 

 wave is gone, which falling is proportionably lefs Iharp as 

 her head is lefs heavy ; the fhake is then Lis violent, fmce 

 fhe (hocks the water with a kfs mafs, which prevents her 

 pitching fo deep as (lie would do, if (lie were more heavy; 

 confcqueutly, the mailing does not fiifler, and the head-way is 

 lefs delayed, as the fulleft part of the bows is not fo much 

 expolcd to the (hock of the water. 

 Vol. Ill, 



B A L 



Secondly, wlien the (hip ia carred by one finHe ware 

 her fall is ftiU lefs fnai-p, if little loaded a-heid, than when 

 (lie is earned only by the middle. She rifcs, therefore, more 

 eafily at the moment the other wave comes to (hike her, and 

 the ftiake is not fo viokiit. Was (lie to plunge deeper into 

 the fluid, it might happen that the column of water would 

 become higher than lar head, and, palSng partly over it, 

 would expofe her to the danger of foundering. 



In the rtowing of the cargo, it is proper to place the 

 heavieft part of the ftowage as low as poffible, titkiiig care 

 to preferve that draught of the fliip which is moft advan. 

 tageous for her, whether (lie be in ballaft or when^ laden. 

 Thofe points are marked both at the head and (Urn: in a 

 word, the great art of ftowing lies, in endeavouring that 

 each of the vertical parts, in which the extremities oFa (hip 

 may be (fuppofed to be equally divided, be lighter, when her 

 lading his complete, than the weight of the mafs of water 

 they are to difplace ; obfcrviiig always, that the vertical 

 parts of the middle admit of being loaded more heavily than 

 the weight of water they are able to difplace. 



In the royal navy, the iron ballaft is firft ftowed fore and 

 aft, from bulkhead to bulkhead in the main hold, next to fir 

 cants nailed on the limber-ftrakes on each fide the kelfon, 

 five or more inches clear of the limber-boards ; and is winged 

 up three or more pigs above the floor-heads in the midftiips, 

 or bearing part of the (hip, and there are two tiers of pig» 

 in the wake of the main hatchway and wcll-wings. Ships, 

 built with a very clean run aft, feldom have any iron ballad 

 ftowed abaft the pump- well or after-hold. Ships that have 

 floor and futtock riders, have the iron ballaft ftowed either 

 lengthways or athwart (hips, agreeably to the length of the 

 chambers, which are the clear fpaces between the riders. 



The (hingle ballaft is next fpread and levelled over the iron 

 ballaft ; on which is ftowed the ground tier of water, bung 

 up and bilge free from the fides, either chine and chine, of 

 bouge and chine, beginning at the coal-room bulkhead, that 

 being the forcmoft, and making the breakage, if any, at the 

 main hatch. The midfliip tiers, fore and aft, are the (irft; 

 laid down, and the cafks are funk about one quarter of their 

 diameter into the ftiingle; the fides arc filled-in with winger* 

 of fmall caflcs, as half-hogflieads, gang cafks, or breakers; 

 obferving not to raife the wingers above the level of the tier, 

 to caufe a breakage in the next tier above, which is ftowed 

 in the cuntline of the ground tier, bung up and bilge free ; 

 and fo on, for as many tiers as can be ftowed fuffixriently 

 clear of the beams. 



In the after hold, between the aft-fidc of the pump-well 

 and tifti-room bulkhead, are ftowed the provifions above the 

 ground tier; between the calks, billet, or other wood, and 

 (hingle ballaft. 



In the fifli-room are ftowed fome of the fpirits, or wine, 

 and fometimes coals ; and in the fpirit room, aie llowcd the 

 v\ine and fpirits for the (hip's ufe. 



In the merchant fervice, the ftowage confifts, bcfides the 

 ballaft, of ca(ks, cafes, bales, boxes, &c. which are all 

 carefully wedged off from the bottom, fides, pump well, 

 &c. and great attention paid that the moft weighty materials 

 are ftowed nearell to the centre of gravity, or bearing of the 

 fliip; and higher or lower in the hold agreeably to the form 

 of the veffel. A full low-built vcffel requires them to be 

 ftowed high up, that the centre of gravity may be raifed, 

 to keep her from roUing away her mails, and from being 

 too llitt and labourfome; as, on the contrary, a narre>w high- 

 built veffel requires the moft weighty materials to be ftowed 

 low down, nearell the kclion, that the centre of gravity 

 may be kept low, lo enable lier to cajiy fail, and to prevent 

 her overfetliog. 



3 U £aJ/aJ 



