[Footnote 18: From the mouth of the Chorera to the Bay Lemon, the distance is 27-1/2 geographical miles. There is, however, reason to believe, that the distance from sea to sea is still less. Ulloa, who was an accurate and scientific observer, places, and from actual observation, Chagres in 9 deg. 18' 40" N. lat., and Panama in 8 deg. 57' 41" N. lat. Not being able to observe an eclipse of Jupiter's satellites, owing to the obscuration of the atmosphere, he was obliged to calculate the longitude from bearings and distances. In these, however, he could not be far wrong; and by these he places Cruces 21' east of Chagre, and Panama 9'30" east of Chagre, which, if he is correct, brings the breadth of the land from the Castle of Chagre to Panama, to be only 23 geographical miles!! Since the preceding pages were written, Captain Washington, secretary to the Royal Geographical Society, has favoured me with the longitudes of the places adverted to, as ascertained by Captain Forster, and in February 1837 by Captain Belcher, R.N. Porto Bello is in 79 deg. 30' West long.; Chagre, 79 deg. 55'; and Panama in 79 deg. 29' 20". This gives the distance from Chagre to Panama 33 geographical miles. Porto Bello is in lat. 9 deg. 32' North. From thence to the Pacific, a little to the east of Panama, is 30 miles. From Chagre to the mouth of the Caymito will be 30 miles. Ulloa's calculations of longitudes would thus appear to be wrong.]