Do not use the sign # before the number of the street address. No letters or sign at all should be used there. See §155.

Compare the following forms of addresses:

Bad: Col. Wm. Point,
#200 John St.,
Trenton, N. J.
Good: Colonel William Point,
200 John Street,
Trenton,
New Jersey.
Good: Colonel William Point
200 John Street
Trenton, New Jersey
Bad: Chas. Jones,
c/o Edward Furrey,
Wilkinsburg, Pa.
Good: Mr. Charles Jones
In care of Mr. Edward Furrey
Wilkinsburg
Pennsylvania
Bad: Rev. Walter Bertin
Good: The Reverend Walter Bertin
Bad: Pres. of Bucknell Univ.
Good: For the President of Bucknell University.
Bad: Pres. of Bucknell Univ.
Good: For the President of Bucknell University.

A properly arranged address:

174. Correctly Written Letters

200 Mead Avenue,
Wilkinsburg, Pennsylvania,
January 12, 1909.
Mr. A. M. Weaver,
Cambridge, Massachusetts.

My dear Sir:

I have received your letter of inquiry about the sale of my law books. I will say in answer that at present I have no intention of selling them.