Filing Index Cards with a C-Line Document Sorter

Not surprisingly, I don’t always file away my index cards as quickly as I probably ought to. Every now and then I go through my deck of unfiled cards and try to sort them into my card index/zettelkasten. The end of the year seems like a pretty good time to clear the decks.

Because I haven’t documented some of this portion of my process before, I thought I’d take a few photos of my C-Line document sorter which I use to do a fast sort of cards before filing into my card index. I bought it a while back from Brodart Library supplies and it comes in quite handy for sorting and filing documents. It’s got sections for sorting by alphabet, days of a month, months of the year, days of the week, and numbers up to 30,000 (which I primarily co-opt for Dewey Decimal sorting). The days of the month and month sections come in handy for use with my Memindex work, and the months of the year are useful for sorting receipts for expenses and at tax preparation time. In all, it’s fairly flexible analog office tool.

Side view of a C-Line index card sorter sitting on a wooden table. We can see about 100 cards slotted into the various flaps of the sorter

As I go through my stack of index cards, I use a Mitsubishi No. 772 pencil (the vermillion side) to underline topics for filing and cross-referencing purposes. This allows me to cross-index topics quickly as well.

A box of Mitsubishi No. 772 pencils with a sharpened one sitting in front of it. One end of the half red/half blue pencil is vermillion and the other end is Prussian blue.

I went through several hundred cards the other day and only had about 150-200 left for filing into the commonplace book section of my card index. Most of these cards were from 2025, but some dated into 2024 with a handful from as far back as 2023. 

Over the coming days, I’m hoping to finish cleaning up some of the notes from this year’s reading work.

Read Principles of Indexing and Filing by Laura H. Cadwallader and S. Ada Rice (The H. M. Rowe Company)
An early 21st century textbook on filing and indexing practices geared toward office workers. First edition, 1932.
The first section is on the rules of alphabetization and indexing to standardize the space of ordering cards for both people’s names and company names.

The second section covers some history on basic filing techniques and then goes into alphabetic, geographic, numeric, and subject indexing methods. The final sections cover the L.B Automatic (Library Bureau), the triple check method, and various other special filing methods as well as maintaining and transferring files for long term storage. Illustrations of these various methods help to visualize how they worked in practice.

This text isn’t as interesting or as comprehensive as the works of J. Kaiser from earlier in the century.

Read on 2025-11-16.