300 Securities against Fire, &c. 
one steam engine, with one vessel alone to carry it? By means of 
two engines, each placed in its own vessel, sharp turns in the naviga- 
tion may be more easily made; in case of an accident also to one 
engine, still the other engine is left to do such duty as the case ad- 
mits; but what is more important than all is, that when sunken tim- 
ber lies in the course of navigation, cords stretched out at different 
depths between the two steam boats, may detect these impediments 
to the navigation of the principal vessel, and give more or less time- 
ly notice of the danger. Indeed even a single steam boat may have 
projecting apparatus at its head, which may of itself furnish an im- 
portant warning.—When danger is lessened, it will soon lessen insu- 
rance, and increase the applications for passages and for conveyance 
of goods in steam boats. 
As to vessels having steam engines on board, and navigating open 
seas, it is plain, that what is done with respect to them, must be con- 
fined chiefly to their steam engines; and to the prevention of fire de- 
rived from the use of them. 
It is doubtless true, that the theory and practice of steam engines 
are still so imperfect, that the government can only make partial, and 
those chiefly negative regulations on the subject of them; but such 
regulations it may make, and (we venture to say) it ought to make, as 
speedily as possible. If wisely framed, they are likely to be copied in 
several other countries, although not perhaps by legislative enactments. 
I have already asked leave to make two tneidental remarks, as 
the sequel of the present article of my Supplement: and they are 
suggested by reflecting on the means of extending the use of steam 
boats. : 
1. The Mississippi and Missouri, with their connected waters, may 
be made equivalent to rail roads by land, if the obstructions to their 
use be removed, by freeing them from sunken trees; and by pre- 
venting new additions to this evil—I do not know whether jointed 
and moveable heavy wooden booms have been used for sweeping the 
bottoms of these streams, but I may enquire whether the cutting down 
and burning of trees liable to be swept down by floods into these 
streams, has been thought of; although the time may come when this 
expedient it will be worth noticing. Steam boats however are now 
said to be used in removing sunken trees. Here our first znczdental 
remark may be left. 
