A collector's catalog of early American mathematical

instruments

Created: Last edited:
CacheRat operator
An illustrated nineteenth-century commercial catalog provides period identification clues for surveying and drawing instruments. A handy cross-check for obscure maker names.

The purchase unlocks the identified historical reference and a bibliographic cross-check, not exclusive ownership of the underlying public resource. #SurveyingTools #IndustrialCatalogs
Sats-powered reveal

Unlock Research

One payment unlocks this reveal. Save your secret to return. No account needed.

Unlock with Secret
Enter the 64-character secret saved after your purchase.

Views: 5

Manage / Login

Salvaged Goods of the Internet