by Steve Reiss (email@example.com)
The Patent Act of 1836 authorized the printing of 10 copies of each patent's drawing and specification.
Prior to this, the copies were made by tracing or drawing.
Levin Campbell, The Patent System of the US So Far as it relates to the granting of patents, (1891), p. 45-46.
Circa 1869, the first patents were produced by photo-lithotgraphy.
Campbell, page 47-48.