Homer Blair Patent Model on Exhibition at University of Minnesota - 1999

The IP Library is proudly the home of the Homer and Jean Blair Collection of United States Patent Models. This collection of valuable nineteenth century patent models, dating from 1842 to 1883, is the generous gift of Homer and Jean Blair. Before the revision of the U.S. Patent law in 1870, inventors seeking a patent for a mechanical device were required to submit with their applications, a model as well as drawings and written descriptions. Models are now required only when the Patent Office feels that the applicant must prove the invention works.

Many models were destroyed in two disastrous fires in the Patent Office, in 1836 and again in 1877, but thousands have survived. At least two items in this collection were rescued from the ashes of the fire of 1877.

Mary Potts Iron

Known as the "Sad Iron", U. S. Patent 113,448, April 4, 1871, was granted to Mary Florence Potts, Ottumwa, Iowa.

The invention is a detachable handle for pressing irons. This permits a person to heat a number of iron bodies on a stove, attach the handle to one and iron with it until it cools, then attaching it to another heated iron body.

The model is 8" x 5" x 6" and has a metal body with a smooth bottom, a gold colored metal latch, and wood handle. The body is filled with a white non-conducting material, perhaps Plaster of Paris. The name "Mary Florence Potts" is engraved in script. This model is in very good condition.

This is the famous "Mrs. Potts' Sad Iron" that was widely manufactured and licensed in the United States and Europe. Her picture was featured in advertising. Her iron was exhibited in the Centennial Exhibition at the Smithsonian and also in the 1976 Bicentennial Exhibition. Mrs. Potts' iron is well known by antique dealers and collectors.



This Exhibit which honors women inventors is held annually by Professor Fred M. B. Amram. He is an award winning professor of speech communication and creativity at General College, University of Minnesota. He has authored books and articles about creativity, women and African American inventors, robotics, and communication. Professor Amram has been curator of several national exhibitions displaying the achievements of women inventors. He has provided worldwide consulting services to industry, government agencies, and educational institutions.

Due to the generosity of Homer Blair and the Franklin Pierce Law Center, the famous "Mrs. Potts' Sad Iron" has been a favorite attraction at the Exhibition which includes portrayals in period dress and manner.

Just after the "unveiling" Mrs. Mary Potts was introduced and spoke beautifully about her experience as an inventor. She was dressed in carefully researched and tailored 1884 garb. Mrs. Potts, a historian and museum curator from the Chicago area, received a standing ovation.

Here we see Mrs. Potts experiencing the excitement of actually seeing the iron up close. She would not touch the model without white gloves. (No one else was allowed to touch the artifact.)

Here is Mrs. Potts with a couple of iron collectors. You can see how the iron was displayed in a sealed display case.

Click here to view an article by Professor Fred M. Amram on women inventors


Professor Amram was quite happy with the Exhibition this year as expressed in these letters to Homer Blair and Professor Jon Cavicchi, J.D., LL.M. (I.P.), Intellectual Property Librarian.

More on the Web about Mary Potts, flat irons and women inventors :




<< Return to Homer Blair Patent Collection