LONDON.- Three very different but equally intriguing 19th century topographical artists star in Bonhams next Travel and Exploration sale in London on 15 September – reminders of the hardship and courage involved in bringing back images of far flung places when the only realistic way to do this was to go out and draw them. Edward Lear – most famous, of course, for his nonsense verse – was also a highly gifted landscape artist and his oil painting of 1871, ‘Sunset on the Nile above Aswan’ glows as the fading light turns the river luminous. The painting is most likely to have been a commission from Ernest Noel, the M.P. for Dumfries Burghs who befriended the artist on a journey down the Nile and would have seen Lear sketching during the voyage. It has been in the family ever since and is estimated at £20,000 – 30,000. Topographical art of an earlier period and a very different style is found in David R