»Ea 20,190^.1 FOREST Alsrt) STHKAM. 498 
CYGNET- 
Cygnet, 
During the winter of igoi-02 there was built at the 
■yard of the Geo. Lawley & Son, C'orp., South Boston, 
Mass., the schooner Cygnet, the plans of which ap- 
pear this week. The builders did remarkably good 
work on the boat, and she is said to be one of the 
finest and most expensive yachts of her size ever built 
in an American shipyard. 
Cygnet was designed by Messrs. Tams, Lemoine and 
Crane for Mr. Arnold Lawson, a son of Mr. Thomas 
W. Lawson, of Boston. The boat was planned to 
he a fast cruiser, and has more than filled these re- 
■quirements, as she has shown good speed and is an 
■excellent sea boat. She is a very handsome craft, and 
,jhas been greatly admired. The overhangs are well 
balanced, the sheer graceful and the rig well propor- 
tioned. The bottom is painted drab and the topsails 
black, relieved by a gold stripe. A narrow copper 
line of white gives a very smart appearance, and the 
teak rail and deck trim make a good finish to the 
.black topsidcs. 
The deck is flush, and below there is cotisiderable 
room which has been well utilized. The cabins are 
well laid out and splendidly furnished. The large com- 
■panionway, which serves as a shelter in bad weather, 
'Jeads below to the chart room, which is on the port 
•side. This room is 4ft. 6in. long and is fitted with a 
sofa, gun rack, book shelves and a chart table with 
drawci-s underneath. Aft there is a large double state- 
room 7ft. Sin. long. On each side is a berth with 
sofas in front. At the end of the berths are hanging 
lockers, and in the center of the after partition is a 
combination bureau and desk. There is a set marble 
wash ba'sin under the companionway. Overhead there 
is a -skylight, which gives light and ventilation. Oppo- 
site the chart room, on the starboard side, is the toilet 
equipped with a set inarble wash basin, and a patent 
water closet, back of these is a roomy locker for 
linen. 
Opening from the chart room is the main saloon, 
which is lift, long and runs the full width of the boat. 
Sofas extend along either side, and behind these are 
lockers and shelves. At the forward end on each side 
are buffets. 
A door opens into the galley, which is 8ft. long. 
Here there is a large ice box, sink, range, dresser, 
dish racks, etc. On the starboard side, leading from 
the galley, is the captain's room, with a swing berth, 
bureau, desk and hanging closet. 
The forecastle is 13ft long, and there is ample room 
-DESIGNED BY TAMS, LEMOINE & CRANE FOR ARNOLD LAWSON. 
Photo by T. E. Marr, Boston. 
for the three sailors and the steward. There is a whole expansion of the steam from boiler pressure to 
water closet for the men and locker room for their condenser pressure takes place in the jet itself, and the 
clothes. total energy is transformed to the velocity of the steam 
Two boats are carried on the davits — a launch to flowing from the jet. 
starboard and a dinghy to port. The second classes of turbines are those known as the 
The principal dimensions follow: parallel flow turbines. Here the plates are set alternately 
I^ength — on the periphery of a revolving comb and a fixed envelope, 
Over all 73ft. Sin. the motion is caused by the sinuous flow of the steam 
L. W. L, 46ft. from plate to plate. In this case the expansion takes place 
Overhang — the turbine itself. 
Forward 13ft. Sin. In either case the turbine principle is entirely different 
Aft 14ft. from that of the reciprocating engine. The turbine takes" 
Breadth — its energy from the velocity of flow of the steam, and the 
Extreme : 15ft. engine from the initial boiler pressure and adiabatic ex- 
L. W. L ' 13ft'. loin. pansion of the steam in its cylinders. Of course the 
Draft— " ' ' velocity of steam flow in the turbine is caused by this 
"Bxtreme loft. 6in. same pressure and expansion, but in one case the trans- 
To rabbet . ... ^. ....... . . V. V. . \ \ . . . . 5ft.' 4in.' formation into mechanical energy is indirect and in the 
Depth *..., 7ft. gin. other direct. The steam velocities are extremely high, in 
Freeboard — ^to top of rail— ' ' the neighborhood of 4,000ft. per second, and as'a turbine 
Forward 6ft. to run with the greatest efficiency tnust absorh this whole 
Least 3ft". lOin. velocity, the peripheral speeds are at the best enormous. 
Taffraii 1 ... . 4ft'. Sin! and greater in the jet turbines than those of parallel flow. 
Ballast '^^^^ revolutions of a de Laval jet turbine of small size 
On keel 25,000 lbs. about 35,000 per minute, and in the larger sizes -froin 
Sail area 8,000 to 10,000 revolutions a minute. 
Mainsail . .... 1,416 sq. ft. This tremendous speed has Compelled the use of a 
Foresail .' '. .' .' '. '. '. .' '.['.'.'.'.['.'.'.'...'... '507 sq. ft. reducing gearing 
Fore staysail 271 sq. ft. In the Parsons turbme the smaller sizes have a speed 
Jib 370 sq. ft. about 3,000 revolutions per minute, and the larger 
'. sizes about 500. 
Total area lower sails 2.564 sq. ft. . A high-speed reciprocating engine of corresponding 
The boat's construction which is rather elaborate ^'^f ^ ^P^^'^ ?^ ^° revolutions per minutd 
Jc Jin 1 I construction wuicn is ratner eiaiwrate, revolutions per minute respectively, or one-fiftlt 
IS clearly shown on the plan of the midship section. ^^^^^ p^^^J^^^ ^^^^-^^^ one-fiftieth as nSiiy 
__ Laval. 
Q, '-p 1, Horse-power, which is the engineer's measure of work 
otCd.ni 1 UrDiricS* done, is a product of two factors — weight and speed or in 
BY CUNTON H. CKANE. OF TAMS, LEMOINE & CRANE. Hons"^ Tl^^m J^'lf^ Ih/S^^^^ '"^ "^°}^' 
' _ . tions. _ Inis mean,s that tor a constant, horse-power the 
In" considering the substitution of steam turbines for tort will decrease in direct proportion to the increase in 
reciprocating engines in marine propulsion, there are of the mimber of revolutions, and as strains are in the main 
necessity many points of view from which the subject dependent on tort, sizes and weights will decrease as 
inay be approached; but there are two chief considera- revolutions increase. We should therefore expect to find 
tions which at once suggest themselves. First, a direct turbines of a given power much lighter than reciprocating 
comparison of turbine and engine in weight,^ size, princi- engines, and as a matter of fact they are so. 
pies involved and general mechanical qualities. Second. The. high-speed engines of torpedo boats and fast j^achts 
the effect on the various elements of the vessel brought weigh about lolbs, per indicated horse-power. Steam tur- 
about by the essential differences, and a summing up of bines about 3 to 5lbs. per indicated horse-power. Engines 
the gains and losses which may be anticipated in various of slower yachts and merchant vessels weigh about 20 to 
cases from the change. 30lbs. per indicated horse-power. 
In the first place, there are two classes of turbines in As regards efficiency, at the full-designed speed the tur- 
successful use at the present time — jet turbines, which de- bine uses rather less steam per indicated horse-power than 
rive their energy from a jet of steam impinging on a the best triple expansion engine, but at speeds less than 
series of plites set on a periphery of the wheel or disc the designed speed, the turbine uses from 10 to 25 per 
on the same principle as water on a Pelten wheel. The cent, more steam per indicated horse-power than the triple 
