US patents for horseshoes with permanent plate and auxiliary tread plate, prior to 1892:

#33709, 48623, 48827, 50952, 56065, 57420, 62076, 74892, 80213, 86014, 142590, 148696, 171626, 199422, 206939, 222700, 246928, 280816, 289402, 294990, 301721, 302185, 303692, 304516, 304853, 308085, 308449, 322652, 334658, 334659, 334660, 337090, 346497, 353354, 365403, 380800, 429460, 435104, 451332

source: www.uspto.gov.