Martha Battle Jackson wrote seeking a source for reproduction of 20th c.
carpeting.  Sorry I haven't got a source for that.

However, I would like to advise against the use of a hair carpet mat.  Is
this meant to be carpet underlayment?  If so, I  strongly recommend against
the use of hair-based underlayment because of the potential for infestation.
 Troy Mills, Inc. 30 Monadnock Street, Troy, NH 03465-1000 USA (Tel:
603-242-7711) produces a white felt constructed on 100% pure polyester fiber
that has been used as a padding under rugs at US National Park Service sites
and is recommended by Jane Merritt, Textile Conservator of the NPS.  The feld
can be purchased in one or two different thicknesses.  The thicker felt
(product no. 1-20-200) might serve as a good replacement for horsehair carpet
pads.  Trpy Mills should be contacted directly regarding pricing,
availability, and minimum order requirements.  Our contact there, Kent Royce,
said that they often combine a number of smaller orders to fulfill the
minimum order requirement.

Wendy Claire Jessup
President and Conservator
Wendy Jessup and Associates, Inc.
210 Little Falls St., Suite 203
Falls Church, VA  22046  USA
(703) 532-0788
(703) 532-1661 (fax)