In order to have the evidence on which to base our entries in a convenient form that can be easily stored and referred to, quotations that include the word to be defined were written out on paper slips, each measuring 10cm × 15cm. The ‘slip-taker’ would decide on what length of quotation is needed to give the necessary amount of text — from the point of view of grammar and sense — to allow the lexicographer to work out the meaning of the word in question. These slips, each with the word to be defined written in the top left-hand corner, with the quotation in the centre of the slip and a precise reference to its source at the bottom are stored in alphabetical order in boxes.

The DMLBS has a collection of well over half a million such slips, contributed by many readers over the decades. The first slips were sent in by voluntary, external readers during the 1920s, who might work in a library, an armchair at home, or atop an elephant in Burma, armed simply with a text, a pen, and a stack of blank slips. When one text had been read, the slips would be sent back to London and another text requested. These slips are still used (albeit sometimes with difficulty on account of the idiosyncratic or old-fashioned handwriting) alongside quotations more recently copied out from new editions of texts, or from modern databases and concordances.