1819.] — Dr. Murray on Muriatic Acid. 285 
possibly acquire a velocity from the lapping of the paddles or 
wheels, there being no taz/ race or declivity to create and keep 
up such a motion. , : 
This point being established, it seems to be conclusively in 
favour of disposing of the wheels of a steam-boat in the form of 
a water-course, as represented in the plan No. 1, and longitudina) 
section marked No. 3, upon the accompanying plate ; and with 
this in view, we do not hesitate to recommend to the attention of 
our readers the construction of the boat here alluded to, as well 
calculated to give much facility in the navigation and birthage of 
steam-boats, and to render them applicable to canal navigation, 
for entering harbours, and sailing in rivers, crowded with ship- 
ping, with the most perfect security; while such a degree of 
convenience and accommodation is afforded to passengers as 
must render the Stevenson Dalswinton Steam-Boat an object of 
very considerable importance on ferries, and on various distant 
assages throughout the kingdom; as, for example, upon 
beeaicterty, Kinghorn, and Dundee, and from Leith to various 
ports on the coast of England, and ultimately to London. The 
same description of boat is well calculated for passing from 
Harwich to Rotterdam, from London to Ostend, from Dover to 
Calais, &c. &c. &c.; such boats are also well calculated to sail 
from Glasgow and Greenock through all the Lochs of Argyle- 
shire, and the Crinan and Caledonian canals, to the eastern 
coast of Scotland ; also to Belfast, Dublin, and Liverpool, and 
upon the great public ferries from Holyhead to Dublin, and 
Portpatrick to Donaghadee. Indeed on many of these passages 
the steam-boat has already been tried, even in its present 
imperfect state, with a good effect; and we despair not of seeing 
this noble invention so much matured that their voyages to the 
distant parts alluded will be made with such a degree of safety 
and dispatch as to render this one of the most valuable improve- 
ments connected with the insular situation of Great Britain. 
Thus if our humble endeavours shall be found useful either in 
advancing the improvement of the steam-boat, or in tracing 
these inventions to their proper authors, our end and object 
will have been completely obtained. 
ARTICLE V. 
Observations on the Chemical Constitution of Muriatic Acid 
Gas, and on some other Subjects of Chemical Theory. By 
John Murray, M.D. F.R.S.E. Fellow of the Royal College 
of Physicians of Edinburgh. 
(Concluded from p, 39.) 
ADMITTING water to be procured from muriatic acid gas in 
those forms of experiment, direct or indirect, in which: the 
