words on the Map which accompanies these journals. It has been
compiled from Dr. Livingstone's original drawings and note-books, with
the corrections and additions he made from time to time as the work of
exploration progressed, and the details of physical geography became
clearer to him. The compiler, Mr. John Bolton[1], implicitly
following the original outline of the drawing as far as possible, has
honestly endeavoured to give such a rendering of the entire work, as
the Doctor would have done had he lived to return home, and
superintend the construction; and I take this opportunity of
expressing my sincere gratification that Mr. Bolton's rare technical
skill, scientific knowledge, and unwearying labour have been available
for the purpose.

Amongst almost the last words that Livingstone wrote, I find an
unfinished letter to myself, in which he gives me very clear and
explicit directions concerning the geographical notes he had
previously sent home, and I am but carrying out the sacred duty which
is attached to a last wish when I call attention to the fact, that he
particularly desired in this letter that _no positions gathered from
his observations for latitude and longitude, nor for the levels of the
Lakes, &c., should be considered correct till Sir Thomas Maclear had
examined them_. The position of Casembe's town, and of a point near
Pambetté at the S.E., and of Lake Liemba (Tanganyika), have been
computed and corrected by Sir T. Maclear and Dr. Mann. The
observations for latitude were taken at short intervals, and where it
has been possible to test them they have been found very correct, but
I repeat that until the imprimatur of his old friend at the Cape of
Good Hope stands over the whole of Livingstone's work, the map must be
accepted as open to further corrections.