----------------------------Original message---------------------------- Susan Greaves Olin Library, Cornell Susan: The current edition-print dates for the sheets you asked about are listed below. I found only two new editions in the listing (and one sheet that was out of stock in Honduras so I don't know the dates). We just got back from Honduras where we purchased some complete sets of 1:50,000 topos so this data should be current. I've never bothered to compare new printings with the original editions to see if there are any updates at all. If you want to send me a copy of one of your 1st edition/1st printing sheets I'd be happy (and curious) to compare it with one of the 1st edition 3rd or 4th printings to see if there are any minor updates incorporated in the new printings. Cheers, Russell Guy Omni Resources [log in to unmask] 2360-I (63) 4th printing 3-86 1st ed. 1963 2360-II (63) 3rd printing 11-91 1st ed. 1963 2361-II (66) 3rd printing 9-94 1st ed. 1966 2459-I (63) 2nd printing 5-73 1st ed. 1963 2459-IV (68) new edition 4-91 2460-I (63) 2nd printing 4-86 1st ed. 1963 2460-II (63) 3rd printing 5-85 1st ed. 1963 2460-III (63) out of stock in Honduras 2460-IV (63) 3rd printing 5-85 1st ed. 1963 2461-1 (66) new edition 4-89 2461-II (65) 2nd printing 10-77 1st ed. 1965 2461-III (65) 3rd printing 3-90 1st ed. 1965 2461-IV (66) 3rd printing 4-92 1st ed. 1966