As presaged in a message in December, I have finally completed indexing our holdings of USGS 24k (and 25k) topos/orthophotos.

Thank you to those who provided feedback at the time.

We have a very incomplete set of these sheets, as the exchange arrangement with USGS, under which this series was received, was cancelled circa 1990 when we began to fully realise how much storage the series would require and how little it actually got used. Our current US 24k holdings occupy about 170 drawers. They are arranged by state, in the same shelf order as the LC G-schedule call numbering for individual states, but apart from Hawaii, all sheets are call numbered using the US number (G3700) not individual state numbers.

I have made an overall US map with some notes about the series, and attached this to our catalogue record https://catalogue.nla.gov.au/catalog/6855508, along with coloured-in USGS indexes of the 49 states that used this scale. While the indexes all use pink for the USGS 24k topo maps, I have used other colours to indicate any USGS or AMS 25k topos (the AMS ones usually using the same state-based series numbering), b/w photomaps, orthophotoquads, or other variants.

The red state boundaries indicate the edges of each state series (i.e. V882 & V082) for Texas, but I came across at least one sheet where the series number changed between editions.

You can click on the thumbnail image of the US in the catalogue record, to bring up that image in our online viewer (where it can be zoomed/panned/printed/downloaded), then click 'browse this collection' in the breadcrumbs at the top left of the viewer, to browse through the individual index images, which have been arranged alphabetically.

I've used older (1970s) paper index for some states, particularly where we hold older editions whose sheet names have since changed. In other cases I've overwritten the sheet names for what we hold on the indexes needed.

Any comments are very welcome, whether complimentary or critical. I'm interested to know if anyone in the U does his differently, but I guess you've each got ocmplte sets for your own states, so don't need to colour the indexes.

It's been a long process (6 months), but I discovered many misfiled sheets (some clever past librarian had carefully filed half of our Missouri sheets in the Montana drawers, because she misinterpreted "Mo."), so it's been good to ensure this series is sorted and ordered and housed properly, and hopefully the online indexes will encourage more use of the series. A least patrons can now see what we've got and request it accordingly – the original catalogue record with no index was rather useless for patrons and retrieval staff alike.