282 Origin of Steam-Boats, and “[Aprit, 
to the operation of the steam-boat on the Clyde, the Forth, the 
Thames, and the Mersey, it has been uniformly observed, that 
the steam-boats are drawn down or made to dip by the head or 
stern into the water, according to the position of the wheels, 
from four to as much as nine inches, which obliges the boatmen 
to trim or ballast with iron at the sternmost point of the boat. 
This, on the whole, must not only greatly impede the motion and 
velocity of the boat; but the whole weight and power also of 
the engine being exerted in one point, a motion is generated 
throughout the vessel, which is not only unpleasant to the 
passenger, but must shake the timbers, and be otherwise 
‘extremely injurious to the boat. To obviate this, Mr. Stevenson, 
civil engineer, proposes, as the reader will observe by Plate XCI, 
to place the two wheels at or near the extremities of the 
boat longitudinally, instead of transversely as at present, by 
which the force of the engine will be more equally divided; the 
vessel will also be kept upon an even keel, in so far as the action 
or power of the machinery is concerned ; and the boat will, 
therefore, pass through the water with less interruption, and 
consequently with more velocity. Further, by employing two 
smaller steam-engines instead of one large one, and placing one 
of these in each compartment of a Dalswinton vessel, the steam- 
boat may thus be rendered extremely commodious, and admit 
of being laid out in neat and commodious apartments for passen- 
gers nearly to the full extent of the length and breadth of her 
deck. Such a construction of boat is also well adapted for carry- 
ing goods and cattle, &c. ona ferry. 
In considering this subject, the writer of this article begs to 
turn the attention of the reader to the accompanying plate, 
entitled ‘ Plans and Sections of Stevenson’s Dalswinton Steam- 
Boat, calculated for the Harbour of Leith, and the Locks of the 
Forth and Clyde Canal;” and here it may be necessary to 
observe, that the term Dalswinton is mtroduced with a view 
to connect the name of Mr. Miller, that ingenious country 
gentleman, both with the idea of the steam-boat, and more espe- 
cially with the double boat, of which he »ppears to have been 
exclusively the inventor, and which in the opinion of many is 
peculiarly applicable to the purposes of a steam-boat. It is also 
necessary to introduce Mr. Stevenson’s name, as we are unac- 
quainted with the precise design of Mr. Miller, who seems to 
have applied the steam-engine to a treble boat. In so far, 
therefore, as we know, the idea of providing the accommodation 
for passengers and goods upon deck, with the machinery below, 
and the wheels placed in the manner proposed in the accompa- 
nying plan and sections, is entirely new. 
Description of the Plate. 
The plan on the plate marked No. 1, exhibits the position of 
the water wheels, steam-engines, and boilers, &c. and repre- 
