08 Skimming Dewey numbers off Web catalogues

DDC is a classification scheme, and a list of items arranged according to this or other scheme, would be called a catalogue. Very often you may not be sure where a particular book should go (more on that anon), so one easy short-cut for us lazier types, is to follow whatever they have done in our favourite large library. With more and more libraries going on-line (they put their catalogues on-line, not the book contents!), we don’t even have to physically visit the library to check their classification. So we can even do our work without the benefit of the original manuals of the DDC.

Let’s take yesterday’s example of Birds (Aves), which as you can see is a special favourite. I have a book with me called “A Pocket Guide to Birds of Gorumara”, which is a small wildlife sanctuary in the northern part of the state of West Bengal in India. From the last post, we recall 598 is the DDC ‘hundreds’ code for Birds, freely supplied for our use by the OCLC on its web-site. The subdivision for geographical areas is 09, and we know 0954 is for South Asia and India (from 954 History). 598.0954 is as close as I can get, therefore, without additional help.

This is where the on-line catalogues come in use. First, I could try searching for “Birds of West Bengal”… getting it from the British Library, www.bl.uk (wonderful things come in simple packages!). Searching for ‘birds, bengal’ didn’t yield much, but ‘history, bengal’ yielded a book with Dewey number 954.14, which hints at 095414 as a possible code for Bengal. So at a first guess, we could settle for a number 598.095414 for my little book. I can do a sort of counter-check by searching for ‘birds, india’ and scrolling down... I get 1,150 results, and I would expect Bengal to come up fairly early down the list since the Dewey number for India would be ...954.. and Bengal comes up in the first subdivision, ...9541... Unfortunately for the best-laid plans of mice and stingy librarians, the general catalogue doesn’t yield too many Dewey numbers: a Birds of Goa has 598.2954799, Birds of Sikkim gives 598.295497, which hints at the use of 598.29... for birds of a region, as well as tells us the Dewey numbers of place for Goa 0954799 and Sikkim 095497. I didn’t find any numbers for Bengal, or Calcutta (only a few of the catalogue entries have DDC numbers), but I did find a Birds of Delhi 598.095456, and Birds of the Western Ghats 598.09547, which gives us Dewey codes of place for the two regions, as well as confirming the alternative of using 598.09... for regional birds. So I guess I’d settle for 598.095414 for my book on the Birds of Bengal.

Another source is the Library of Congress www.loc.gov , which seems a bit faster and to have a higher proportion of records with Dewey numbers (just my impression). This one also yields a book on Islam in Bengal 954.14, confirming our Place number, and Birds of North India 598.0954, Birds of Southwest India 598.09548, Birds of Sikkim 598.295497. Thus numbers of Place are consistent, and again both conventions are used: 598.29... and 598.09... You may take your pick... I probably would settle for staid old 598.09..., as it falls into a predictable pattern when you don’t have the manuals at hand.

The on-line catalogues also yield up other interesting numbers, allowing us to build a picture of the structure without help from OCLC. Just searching for “birds” yields 28284 records in loc.gov, and it’s only by the 10^th page (each with 50 records) that we get off just “Birds” as the title (all DDC 598), to something titled “Bird life” with DDC 598.2. This is followed by “Sea birds” 598.2924, which tells us that 598.29 is a special category that has not only geographical names from 598.294 onwards, but also special connotations under 598.292, and possibly 598.293. “Bird watching and bird behaviour” is given 598.2 (which doesn’t look convincing), and “Birds’ nests”, 598.2564. And thus it goes...

Why this elaborate exercise? It gives us ready-made numbers, and it yields us new numbers when we don’t have access to The Book. One really tedious thing is that the records don’t display the DDC number up front... you have to click on each book and call up (display) the individual record. And even then most of them don’t even have the Dewey number entered!

PS: I just discovered Dewey offers a book-by-book service in their site www.classify.oclc.org... check it out! You have to click down to a single book record to see the suggested DDC 'class number' (it also gives the LC number for that book).