Detective Agency Yellow Page Ad, Denver Colorado, 1931
Note the fact that Powell National Detective Agency offered
what was called Dictograph
Services.Click on the blue link to learn all about what the Detective
Dictograph was. Since Dictograph services is listed first and in
all caps, you can assume this was a big thing for the agency. The Dictograph
at the time was a modern, new age, high tech audio listening device
that was the marvel of it's time. The agency was founded, according
to the ad; in 1910. In 1931, they had thus been in business for 21 years.
Mr. Powell was likely very well established. Note the wordage "Frequently
Using Camera" and "Conducted Without Publicity". It's
interesting to note that Powell National Detective Agency listed "employee
investigations for firms and corporations" at this time period.
In this era, surveillance was called shadowing. Note that this ad listed
a main number and then three separate telephone numbers below for after
hours calls. William Powell's home address is listed in the 1931 Denver
phone book as (and we quote)
W 12th And Wadsworth Av TAbor 6975
Since four phone
numbers were listed, you can assume that this agency did NOT want to
miss any phone calls. Remember, there was no such thing as call forwarding
nor answering machines for this time period. It's interesting to note
that the agency listed Blackmail, Kidnappings and murder as investigative
services. Although there were some international and national associations
of this time period, we are not sure what "associates in major
cities" means. However, investigative services like this had competition
like Pinkerton's National Detective Agency that had offices in every
The Ralph D. Thomas PI Vintage Collection
THOMAS INVESTIGATIE PUBLICATIONS, INC.
NATIONAL ASSOCIATION OF INVESTIGATIVE SPECIALISTS, INC.
SPY EXCHANGE AND SECURITY CENTER
P O Box 82148, Austin, Texas 78708
Showroom: 9513 Burnet Road, Austin, Texas 78758
Phone 512.719.3595 Fax 512.719.3594
To The Spy And PI Vintage Pages
2006, Thomas Investigative Publications, Inc. All rights reserved.
Thomas Investigative Publications, Trademark, 1981.
National Association Of Investigative Specialists, Inc, Trademark, 1986.
Spy Exchange, Trademark, 1999