Travels was published in early 1799 by London's W. Bulmer and Co. There were two other Bulmer editions that year with a fourth in 1800, a fifth in 1807 and a sixth in 1810. The title page from the sixth edition is below. These were all quarto or octavo editions that sold to the upper-middle and upper classes.
In 1839 Edinburgh's William and Robert Chambers published a much cheaper edition in wraps as part of their series The People's Edition. The full text plus supplemental material was printed on 88 double column tiny type pages. The book is 162mm x 250mm. Note that the date is wrong for the first edition.