xxiv INTRODUCTION. 



over- ruled by the ^vell known fact, that on the banks of the 

 lower parts of the river are whole forests of the mangrove, 

 the wood of which possesses the peculiar quality of burning 

 in its green state better than when dry ; but it was not 

 known to what extent these forests might reach, though 

 it was fair to presume, that, in an equinoctial climate, 

 where water was to be found, wood would not be wanting. 

 At the same time it could not escape notice that the labour 

 of felling and preparing fuel for the boiler of a steam 

 eno-ine to the amount of about three tons a day, in such a 

 climate, might be fully as fatiguing, and in all probability 

 more fatal to the crew, than the occasional operation of 

 rowing. If, however, it could have been certam that this 

 vast and rapid river was navigable beyond the cataracts, 

 and its banks well wooded, a steam engine might prove 

 a good auxihary ; and accordingly it was determined that 

 a vessel, capable of being navigated b}' steam should forth- 

 with be constructed. 



But another difficulty presented itself The vessel was 

 not only to be constructed so as to be adapted to the flats 

 and shallows that might occur in the river, but so as to 

 ensure her a safe passage across the Atlantic ; this was 

 thought by many persons to be no easy task. The burden 

 of the vessel was not to exceed one hundred tons, her 

 draft of water four feet : of this tonnage it was calculated 

 that the engine of 24 horses power would alone occupy 

 one-third part, and, of her measurement, the whole breadth 

 of the vessel, and twenty feet in length. Such a vessel, 

 however, with so heavy a burden and so small a displace- 

 ment of water, Mr. Seppings, the surveyor of the navy, 

 undertook to construct, and at the same time to give her 



