OK - now that I have a few non-trivial chunks of therion data to bring together I have re-arranged everything in a big-cave way. This has of course caused some problems. I am documenting them here. What I want to be able to do is produce a whole area map as well as smaller maps of each cave in the area, and maybe parts of a cave, and keep related data together,but only have it appear in one place. I know how to do this in survex, using a directory for each major cave or area. That contains an 'overview file' that is something like: *survey terikan *equate elevator.pt3.18b evening.25 *include elevator.svx *equate river.40 goon.0 *inculde goon.svx ... *end terikan so connections between surveys are here, but not connections within surveys (they are inside each .svx sub-file), and also connections (equates) are grouped together with the relevant files. So, I have an overall file for terikan in therion form but if I try to use the above structure - i.e like this: survey terikan map <scraplist> endmap input elevator.th2 input goon.th2 ... join <whwatever> centreline equate 0@goon 40@river input goon.th equate 25@evening 18b@pt3.elevator input elevator.th endcentreline endsurvey terikan then I get an error: therion: error -- terikan/terikan.th [72] -- not enough data readings at the first line that is an 'input <something>.th' The only way I can get it to work is by moving all the equates into one block, wrapped in a centreline/endcentreline command But for a big system this gives you a huge list of equates in one place and ahuge list of inputs below - it'smuch nicer to have the equates in the file next to the relevant inputs IMHO. So questions: 1) is my preferred arrangement possible/permitted in therion? How do would one do it? 2) Why do I get the error 'not enough data readings'? That seems to have very little to do with the actual problem - it took me some time to work out how to make it go away. I have more questions about arranging scraps and submaps too, but those can wait till another mail. Wookey -- Aleph One Ltd, Bottisham, CAMBRIDGE, CB5 9BA, UK Tel +44 (0) 1223 811679 work: http://www.aleph1.co.uk/ play: http://www.chaos.org.uk/~wookey/