Chapter II — Patent Grants
United States Patent Office
The Cyanotype Era, 1870–1915
The Diagram Outlasts the Machine
US Patent Grants by Decade, 1870–1915
Fig. 1 — Cumulative Grants Filed, United States Patent Office
400K
300K
200K
100K
0
126K
208K
235K
264K
372K
+195% vs. 1870
1870
1880
1890
1900
1910