This set of notations consists of 15 sheets that were numbered consecutively as Sheet 1 - 15 by Babbage, as well as 25 loose enclosures in the format of strips of paper of varying sizes, stored in an original envelope with its original label intact.
The label describes Notation 290 and the enclosures as follows '15 Sheets besides the contents viz. 21 pieces explaining the different verticals and orders necessary for common division; 15 strips exhibiting the verticals required for governing the counting apparatus when two barrels are used for that purpose. All belonging to Notation 290.'
The full number of pieces and strips are not available, nor is it clear which of the existing 25 enclosures are pieces or strips, as described by Babbage, or how they match with the original description. The strips appear to be draft calculations relating to the different sheets.
Bromley numbered the strips consecutively as F.290/ to F.290/. Babbage numbered some of the strips in pencil, namely 1 (F.290/ and F.290/, 2 (F.290/) and 4 (F.290/ - F.290/). These probably relate to sheets 1, 2 and 4. Strips F.290/ to F.290/ are all described as 'One barrel to order common division' and include a reference to the relevant corresponding sheet. All the strips are undated with the exception of F.290/, which is dated 22 September 1836. The dimensions of the sheets, which are all quite narrow, vary from 3cm to 25 cm x 18cm to 53 cm.
fifteen sheets and 25 loose enclosures
- Large Format Document