Location:

1718 Land Title Building, Philadelphia, PA (1906-1909) [factory?]
134 North 10th Street. (1910-1914)
327 North 11th Street. (1915-1923?)
1914: La Porte, Indiana. Eastern office and second factory in New York, branch offices and warehouses in Philadelphia and Chicago.

Timeline:

1900 CD (Philadelphia City Directory): Charles H. Paschall (C. H. Paschall & Co.), 1118 North 40th Street
C. H. Paschall & Co. (Chas. H. Paschall) brokers, 1210 Market Street
1905 CD: Charles H. Paschall, salesman, home 4913 Warrington Avenue
1909-1909 CD: American Three Way Prism Company, 134 North 10th Street. Charles H. Paschall, President; Charles H. Hudnut, Secretary; L. Beatrice Paschall, Treasurer.
1910 CD: American Three Way Prism Company, 134 North 10th Street
1914 "F. A. Flocken is assistant manager of the American 3 Way Prism Company, which is moving its offices and factory from Chicago to La Porte, Ind. His address will be La Porte after April 1st." --Cornell Alumni News, Vol. XVI, No. 20, February 19, 1914
1915-1921 CD: American Three Way Prism Company, 327 North 11th Street
Jan 1, 1920: Merged with Luxfer forming American 3-Way Luxfer Company.
So why is it still listed in the 1923 CD: American Three Way Prism Company, 327 North 11th Street; Chas H. Paschall, President (home Chicago); C. P. Mills Vice President; J. J. Ohles, Treasurer.

The American 3-Way Prism Company was Luxfer's main competitor of the time. They eventually bought out Luxfer in 1920 and became American 3-Way Luxfer Prism Co.

ATLANTA, GA., Pittsburg Plate Glass Co.		KNOXVILLE, TENN., The Breese Bros. Co.
BALTIMORE, M.D., Dietrich Bros.	LONDON, ONT., Hobbs Mfg. Co.
BIRMINGHAM, ALA., Wimberley & Thomas Hardware Co.	MEMPHIS, TENN., Memphis Paint & Glass Co.
BOSTON, MASS., Lombard & Tracy	NASHVILLE, TENN., Warren Bros.
CHARLOTTE, N. C., J. H. Wearn & Co.	NEW YORK, N. Y., Pittsburg Plate Glass Co.
CHATTANOOGA, TENN., Price Evans Foundry Co.	OKLAHOMA CITY, OKLA., S. H. Hanson
CHICAGO, ILL., Fred Liebrich	OMAHA, NEB., Midland Paint & Glass Co.
CINCINNATI, O., Pittsburg Plate Glass Co.	PITTSBURG, PA., Pittsburg Plate Glass Co.
DAYTON, O, The Lowe Bros. Paint Store Co.	SAN FRANCISCO, CAL., Waterhouse & Price
DECATUR, ILL., Morehouse & Wells	SPRINGFIELD, ILL., Capital City Concrete Con. Co.
DENVER, COLO., Colorado Brick Supply Co.	ST. LOUIS, MO., Pittsburg Plate Glass Co.
GREENSBORO, N. C., Guilford Lumber Co.	SYRACUSE, N. Y., Joseph M. Hill
INDIANAPOLIS, IND., Hetherington & Berner	VANCOUVER, B. C., Wm. N. O'Neil & Co.
KANSAS CITY, MO., Winsborough Bros.