XXVI INTRODUCTION. 
difference in the application of its power; but the season 
for the departure of the expedition had arrived, the month 
of January had already expired, the officers and men of 
science were all engaged, the articles for presents pur- 
chased, the instruments prepared, and it was most de- 
sirable that the expedition should reach the coast of 
Southern Africa not later than May, or June at farthest, in 
order that the voyage up the river might commence with 
the early part of the dry season. 
Mr. Seppings and Captain Tuckey were both of opinion 
that, with a trifling alteration, the Congo (for so she had 
been named,) might be converted into an excellent sea 
vessel, and equally proper for ascending the river by the 
ordinary means of navigation, namely, by sail and oar: 
and as far as the river navigation was concerned, they were 
confirmed in this opinion. by information collected from 
the master of a merchant vessel, who had been several 
voyages up the Zaire to the distance of 140 miles from its 
mouth, and who stated that he had never found the least 
difficully in ascending witha schooner to that distance by 
the assistance of the sea-breeze, which sets in regularly 
every day ; the current of the river seldom, by his account, 
exceeding five miles an hour in the dry season, and in 
many parts not running more than three. 
The engine was accordingly removed without delay 
from the Congo, and sent, where it was much wanted, to 
the new works at Chatham dock-yard ; the proposed alte- 
ration was immediately made, and on trial of her qualities, 
Captain Tuckey reported, that “he had no hesitation in 
saying, that she was, in every respect, fit for the business.” 
The contrary opinion had been held by many sea officers, 
