[Correspondence]

E&MP 94.016

Photo Electric Cells

February 9, 1935

Mr. John H. Crider
29 De Kalb Avenue
White Plains, N. Y.

Dear Mr. Crider:

This is to acknowledge your letter and manuscript mailed January 31, regarding the Teletector.

I hope to blend the material in your story in with another device of a somewhat similar nature and use the two stories as one.

You will hear from me the latter part of next week regarding our use of this manuscript.

Very truly yours,
Robert D. Potter

[Correspondence]
Feb. 9, 1935
Warden Frank D. Whipp
Illinois State Penitentiary
Joliet, Illinois

Dear Warden:

I am sorry to trouble you again, but the four photo- graphs regarding the detecting device installed in Illinois State Penitentiary have not been received. I refer to the pictures mentioned in your letter to me of January 14.

If other prints of these photographs are available, would you send another set to me?

Very truly yours,
Robert D. Potter

[Correspondence]
January 17, 1935
Paul W. Koch & Company
20 North Wacker Drive
Chicago, Illinois

Gentlemen:

I have received today a letter from Warden Frank D. Whipp of Illinois State Penitentiary discussing the apparatus for detecting guns, knives and other metal in possession of visitors who call at the prison.

His letter informs me that your company manufactures this equipment.

We are interested in preparing a short article for our magazine Science News Letter regarding the operation o this apparatus.

Would it be possible to secure a few technical details on this subject.

Warden Whipp is sending on four photographs as installed at Illinois State Penitentiary.

They will serve as valuable illustrative material for this contemplated article.

We shall be only too glad to give credit to your firm as the manufacturer of this equipment.

Very truly yours,
Robert D. Potter Science Service

[Correspondence]
Jan. 12, 1935
Warden Frank D. Whipp
Illinois State Penitentiary
Joliet, Ill.
Dear Warden Whipp:

After reading a newspaper story on January 7 about the strange case of Thaddeus Johnson, negro trusty at Illinois State Penitentiary, I have been curious to learn more about the new detector system which formed the basis for the story.

Because we publish a weekly magazine on science and engineering developments entitled Science News Letter, I would like to obtain the name of the manufacturer or inventor of the device.

It would then be possible to write to him and obtain the technical details which we would like to print.

If the device is patented, I suppose that we can obtain this information through the U. S. Patent office here.

If you would be willing, it would be highly desirable to obtain from you a short statement of the usefulness or success of this apparatus for the purpose in which it is used.

Very truly yours,
Robert D. Potter Staff Writer Science Service

Original Caption by Science Service