I 
4 
DESCRIPTION OF COMPARATIVEH PLANS 
OF STEAMERS, TUGS, & TOW BOATS, 
ESTABLISHED AND PROPOSED 
ON THE BENGAL RIVERS. 
Comprising shear and deck plans on a scale of 40 feet to an inch; with diagrams 
of their midship sections on a scale of 4 feet toan inch; also on same scale, a 
Shear and deck plan of the bow and ufter-body of the Nautilus system of Tug 
and Tow Boats, with their special fitlings and mode of connection by Tow spar, 
with Low and stern rudders acting simullaneously. 
Scare or Toxxaot Disrtacemust, 
4 On'tho left hand corner of the drawing there aro given curyes of displacemonts for exch of tho vessols shown 
in the drawings. Tho perpendicular scale is ono of draft of water in feot and inches. ‘Tho horizontal ono of roxs oF 
DIAFLACEMEST. 
‘Tho conve ov nisriacaexr is formed hy setting off on tho perpendicular and horizontal scales tho draft of 
water ip feet, and the calculated displacement in tons at threo different depths of water, or height of deck. Lines 
from those points, perpendicular to their respective ecales, oro drayn out until thoy, intorscot cach other, that is, 
until tho Horizontal water line crosses the perpendicular tonuage line due to it. A curve run through these three 
ints of intersection will enable tho displacemeat duo to any draft of water to be readily ssccrtained without the 
Aid of caloulation, 
‘The namo of tho yessel to which it belongs is written on cach curyo, and also at the point on tho draft of water 
scale whore the light draft of each vessel is indicated when Gtted for service and boforo receiving cargo, On the hori- 
zontal or tonnage scale tho name of the vessel is written alung tho perpendicalar dotted lino which intersects the curva 
of displhcements atthe 3 fect load line. ‘The tonnage displacement duc to it being indicated on tho horizontal scale. 
Tho carapitiry yor nrap wefonr canco, marked © WO at 3 feet, is ascertained by deducting tho, displace- 
mont atithe light draft water line in tons from that indicated ou the horizontal lino ut 3 feot load draft of water. 
On the pracnast ov stpsmr accrioss tho displacements are recorded below the 2nd, 3rd, and 4th fect wator 
Hines of each yoasel whoso light draft is loss than 2 foot. ‘The ight water Jine or draft dua to tho weight of tho veascl 
is marked in dotted lines and tho weight of the bull bolow it, skewing the draft of water without cargo. 
On tho peck rraxs are recorded the Mediam Height of deok, tho Tonnage, Old or Builder's Measuroment, the 
External Bulk, and the Ratio betwoon them, or tho number of cubje feet duo to one ton of builder's measurement. 
There is also given tho capability for dead weight cargo\at 2 andat 3 fect, os obtained by deducting tho weight of 
‘vessel, rooorded below the dotted line (on tho midship sections), from: the displaccment, recorded belaw the 2nd and 
3rd fect draft water lines. Fixaxce (on the deck plan}—thore is. Sratescmxz of the amount of capitat expended per 
ton of cipability for weight cargo, shoving how the cost of capability increases with tho diminution of tho draft — 
‘Assam Tog and Tow Boat, capital expended «£19,738 
Lnaded to 4 ft. G.W. C., 231 tons, capital - = es 60 per ton. 
D df. , 100 tons, capital Se = x 137 capability. 
Ganges Steam Company, 5 Iargo steamers, capital expende wo £06,738 
Patna pag W.G. 140 tons, cost £51 per ton Mirzapore, O.W oy 395 tons, cost BS nt 4 ft. 
Benares{ ,,. 23 toms, cost £508 capability } Ghazaporo, ,, J 113 toms, cost 263 at d ft. 
Navriwws Frorixa or Stkaa Too Avo Tonite Tow Boars, rmovosep uy Axpkew Hexornsox. 
“At tho lower part of tho drawing thors is a shoor ani-dook plan of tho stern and bow of tho proposed Neatitus 
steam tug and tow boats for general purposes, . Te will bo seon that the togging pust on bonnd the steamer is situnted 
about half a-breadth in front of the stern, and that the towing post or pivot of the tow boat is placed over thie cut- 
Grater: the two pivots are counceted by a wooden spar which bras a circular head playing on tho post of the stoamer, 
‘and has parallel jaws embracing tho towing post of the tow boat, By this means collision, is prevented botwoon the 
bow of ona vessel and the storn of the other, while tho hawscrs, which arc shewn as passing over friction rollers oo 
the tawipgypost and connecting spar, when relaxed allow tho two vessels to separate to whatever distance’ may bo 
required to enablo them to stesr themselves independently by means of the fora and) uft rndders with which thoy are 
provided. |Theso rudders, as will bo sccn, aro capable of being tilted out of tho wator im tho samo way as those 
described in the nativo boats 
‘Ais it is intended that theso tug and tow boats shall bo capable of being, whou-oceasion requires, manageable 
by native crévrs, there aro special adaptations of the native fittings with regard to propuléion. It willibe sven that 
there is p gunrd boaril or gangway where the crew can make uso of poles whon tracking is impracticable, and also a 
<eries of Chinese seulls which can. be worked with great advantage in narrow channols where other moans are 
difficult of application, ‘The speciality of these Ohincso sculls is that their action is continuous und not inter 
‘as with other sculls; i0 fact, they constitate crow propellers with a variablo pitch adapted to tho speed, nnd w' f 
aroreadilysrorked Uy human labour. This isa peculiarity which is well adapted for the vessels intended for the 
conveyances of troops in India, when the'soliiers could, on an emorgenoy, propel themsdlyes, even without the aid of 
steam power. 
‘Arréference to the midship section of the “Nautilus” in tho diagram of sections will show how it is proposed 
to strengthen tho yesscl longitudinally, by turning in the top plato, and by placing foro and) aft wooden. stringer 
Overt. The deck housos and their framings aro also made subsorvient to their longitudinal/strongth. 
Tn tho sheer and deck plans of the samo vexscl, the hull will be seen to bo divided into threo sections, tho 
middle ono having a double bulkhead intsnded us a well. ‘Tho Hogive is placed above the deck of tho middle 
compartinent, while the fucl and boilorsare situated below. Tt may be deemed advisable to hare small donkey engines 
Placed in the sloramoat compartment, s0 that if nocossary thoy might bo cmployed in working tho Inrge sculls already. 
Fiferréd to, in cases whero the middlo compartment was dispensed with, and the fore and aft compartments above 
Constitated thu whole length of ths vesacl. Tho soparate pieces aro also capable of being employed as pontoons in 
military operations. 
Theso vessela are intended in tho Grst placo to moot the requirements of the railway, companies, and having 
folfilled their functions in this respect, to be banded over to Government so as to form the nucleus of w sinirARy 
Waren maxsronr senvior. Thoy msy also bo employed in all cases whero native boats aro now used, By iron 
frames and fittines being sent from this country to tho, upper provinees, their bottom and sido may bo filled with 
elench-built planie like tho Forruckalud Katoora, forming’ light draft and cheap bont. 
VISANOIAL STATEMUNT NAUTILUS VLOTILLA, ONN TOG AND TILLEL TOW OATS 
Estimated capital or cost complete at Calcutta, £6,000 to £8,000. , 
Loaded to 4 fe. U.W,0, 376 tons Capital £18 por ton} Loaded to 2 . C.W.O, 91 tons capability, at n 
Als [eizergee eel th Fy Th) cost or oapital £77 per ton, 
