DIAGRAM No. 1. Figure 1 represents the after-end of a ship or steamer of the largest class, showing the point from which the register and tonnage lengths are measured.

Figure 2 represents the midship section of a ship or steamer in which the depth exceeds sixteen feet. The upper spotted line, marked No. 1, represents the upper breadth drawn through a point which is determined by setting down from the top of the beam the one-third of the round of the beam. It is from this point, in each area, that the respective depths are measured to the average thickness of the ceiling at the inside of the limber-strake; the last breadth prescribed by the rule is at the lowest point of the depth, and is marked No. 7, and this breadth extends as far as the floor is perfectly flat or horizontal. The midship area alone is here represented, the breadths and depths in each area being taken in precisely the same manner.

Figure 3 represents the forward end of the ship, showing the points from which the register and the tonnage lengths are measured.

Figure 4 represents, on a large scale, the manner in which the length at the tonnage-deck is determined, both forward and aft.

DIAGRAM NO. 2 represents the length of a vessel of the sixth class, in which the tonnage length is divided into sixteen equal parts, showing the inside of the inner plank or upper side of ceiling at limberstrake, above tonnage-deck, and upper side of beams at middle line of ship, and the medium height of beams, or a line set down at one-third of the round of the beams from the upper side of beams just mentioned. There is also represented the breadths directed to be taken for each area, and their position in relation to the depths.

DIAGRAM NO. 3 represents the curve of areas formed by ordinates in proportion to the area of the corresponding sections.

Its construction is as follows: On the straight line are set off the exact position of the areas, according to the length of the vessel; on these stations, marked 1, 2, 3, etc., are set off, at right angles from the straight line, on a reduced scale, in order to bring the figure within manageable dimensions, which, in this example, is one-eighth of an inch for every fifty square feet,) the number of feet in the respective areas or ordinates, ascertained by the rule, and through the points so given the curve is drawn as represented in the figure. This curve of areas, being a continuous and fair line, is a test of the correctness of . the measurements, and an error in computation will be immediately detected. It will be observed that the curve meets the straight line at the stations 1 and 17. This must necessarily be the case; for the areas 1 and 17, being at the extreme ends forward and aft, are equal to zero, and therefore there is nothing to set off from the straight line at those places.

The measurements from which the several transverse areas are obtained, being set off at each station at their proper distances asunder, the forms of each cross-section will be reproduced, and an error in measurement will be at once detected.

DIAGRAM No. 4. Figures 1 and 2 indicate the mode of admeasuring the closed-in spaces above the main deck of river and sound steamers of the Atlantic coast, of which X Y is the upper deck to the hull.

The tonnage of the freight-room in this case consists of the space from A to B, together with the spaces from B to C, less the spaces occupied by the engine, and the galley or cook-room I.

The tonnage of the cabin is to be computed separately. The rooms G and H, abaft the wheels, are to be admeasured if available for cargo, stores, passengers, or crew.

DIAGRAM No. 5 explains the mode of admeasuring the side-wheel steamers of the western rivers. See Article 132.

STAYS AND STAY-SAILS.
[From Webster's Dictionary.]

a, foretop-mast-stay sail; b, maintop-mast-stay sail; c, maintop-gallant-stay sail; d, main-royal-stay sail; e, mizzen-stay sail; f, mizzentop-mast-stay sail; g, h, fore, main, and mizzen-top-mast and top-gallant-mast back-stays; i, fore-stay; j, main-stay; k, mizzen-stay.

1, flying jib; 2, jib; 3, foretop-mast-stay sail; 4, forecourse; 5, foretop sail; 6, foretop-gallant sail; 7, fore-royal; 8, fore sky-sail; 9, fore-royal studding-sail; 10, foretop-gallant studding-sail; 11, foretop-mast studding-sail; 12, maincourse; 13, main-topsail; 14, maintop-gallantsail; 15, mainroyal; 16, main sky-sail; 17, main-royal studding-sail; 18, maintop-gallant studding-sail; 19, maintop-mast studdingsail; 20, mizzen-course; 21, mizzen-top sail; 22, mizzen-topgallant sail; 23, mizzen-royal; 24, mizzen sky sail; 25, mizzen-spanker.

INDEX.

Acids-how to be carried on passenger vessels, § 4472.
mode of packing, § 4475.

punishment for unlawful shipment, § 4476.

Advances-of seamen's wages, before whom made, § 4532.
Advertisement-of notice of seizure of vessel, § 4379.
of prize sales by marshal, § 4628.

for contract for election of light-houses, § 4667.

Agents-of owners, registry of vessel by, § 4161.
oath to be taken by, § 4161.

surrender of old certificate by, § 4162.
forfeiture for false oath by, § 4163.

when to countersign certificate of measurement, § 4181.
of vessels, to furnish copy of consular receipts, § 4213.
Alaska-nationalization of vessels owned in, § 4140.
regulation of coasting trade with, § 4358.

Allotment of wages-to be inserted in agreement, § 4531.
American Colonization Society-passenger vessels of, § 4271.
American seamen-see SEAMEN.

American vessels-when not to be registered, § 4135.
Animals-regulations in transportation of, § 4386.

to be fed and watered, § 4387.

penalty for neglect, § 4388.
penalties, how recovered, § 4389.
lien, how enforced, § 4390.

Anti-scorbutics-to be served on merchant vessels, § 4569.

penalty for neglect, § 4570.

Appeal-to supervising inspectors, § 4452.

Appeals-in prize causes, § 4636.

powers of district court after, § 4637.
security for costs, § 4638.

costs and expenses on, § 4639.

Appraisers-in prize cases, § 4615.

of property taken for Government use, § 4624.
of property delivered on stipulation, § 4626.
Apprentices-shipping commissioners to procure, § 4509.
indentures of, to be produced, § 4510.

articles, of vessels in coasting-trade, § 4520.

wages not dependent on freight, § 4525.

wages not subject to attachment, § 4526.

disposal of effects of, § 4538.

duties of consular officer, § 4541.

wages on death of, § 4542.

payment to circuit court, § 4543.

distribution by circuit court, § 4544.

Apprentices-Continued.

unclaimed wages and effects of, § 4545.
fees of commissioners for shipping, § 4592.
offenses of, and punishment, § 4596.
arrest for desertion, $ 4599.

penalty for drunkenness and neglect, $§ 4602.
enforcement of forfeitures, § 4603.

liable for expense of conviction, § 4605.
form of account of, § 4612.

Appropriations-for light-house sites, § 4660.
for salaries of assistant inspectors, § 4461.
Assault-on officers by seamen, § 4596.
Assignment-of prize or bounty-money, § 4643.
Assistant inspectors-appointment, salaries, § 4414.
Attachment-seamen's wages not subject to, § 4536.
apprentice's wages not subject to, § 4526.

Auction-of prize property, when, § 4627.
mode of making sale, § 4628.

commissions of auctioneers, § 4650.
of effects of deceased seaman, § 4538.

Bail-when refused from seaman, § 4558.
Barges-provisions for security of life on, § 4492.
Beacons-when to be erected, § 4661.

when cession of site deemed sufficient, § 4662.
preliminary surveys for, § 4663.

materials for construction or repair, § 4666.

Benzine and benzole-passenger vessels not to carry, § 4472.
how packed and marked for shipment, § 4475.
punishment for unlawfully shipping, § 4476.
Berths-on passenger vessels, dimensions of, § 4255.
Bids-for light-house contracts, § 4665.

Bill of sale-to recite certificate of registry, § 4170.
to be recorded, § 4192.

to be acknowledged, § 4193.

records of, to be indexed, § 4194.

fee for furnishing copy of record, § 4195.

interests to be set forth in, § 4196.

fees for recording, etc., § 4382.

Births-on vessel to be recorded in log-book, § 4290.

Blasting oil-not to be shipped on passenger vessels, § 4278.
how packed and marked, § 4279.

State regulations of traffic in, § 4280.

Boarding-officers-to report violations as to crew-lists, § 4575.
crew lists and crew to be examined by, § 4576.

Boarding vessels-by unauthorized persons prohibited, § 4606.
Boilers-see INSPECTORS.

Boilers-inspection of, § 4418.

control of safety-valves and steam-registers, § 4419.
pressure on, § 4420.

certificate of inspection of, § 4421.

how inspected, §§ 4426, 4427.

to be constructed of stamped plates, § 4428.

penalty for neglect, § 4429.

not of riveted iron or steel, when may be used, § 4429.