ustomers (Walling _v._ Jacksonville Paper Co., 317 U.S. 564
(1943));

(5) employees of a private corporation who are engaged in the operation
and maintenance of a drawbridge which is part of a toll road used
extensively by persons and vehicles traveling in interstate commerce,
and which spans an intercoastal waterway used in interstate commerce
(Overstreet _v._ North Shore Corp., 318 U.S. 125 (1943));

(6) a night watchman employed in a plant in which veneer was
manufactured from logs and from which a substantial portion of the
manufactured product was shipped in interstate commerce (Walton _v._
Southern Package Corp., 320 U.S. 540 (1944));

(7) employees putting in stand-by time in the auxiliary fire-fighting
service of an employer engaged in interstate commerce (Armour & Co. _v._
Wantock, 323 U.S. 126 (1944));

(8) warehouse and central office employees of an interstate retail chain
store system (Phillips Co. _v._ Walling, 324 U.S. 490 (1945));

(9) employees of an independent contractor engaged in repairing
abutments and substructures of bridges which were part of the line of an
interstate railroad (Fitzgerald Co. _v._ Pedersen, 324 U.S. 720 (1945));

(10) maintenance employees of an office building which was owned and
operated by a manufacturing corporation and in which 58 per cent of the
rental space was used for its central offices, where its production of
goods for interstate commerce was administered, managed and controlled,
although the goods were actually produced at plants located elsewhere
(Borden Company _v._ Borella, 325 U.S. 679 (1945));

(11) the employees of an electrical contractor, locally engaged in
commercial and industrial wiring and dealing in electrical motors and
generators for commercial and industrial uses, whose customers are
engaged in the production of goods for interstate commerce (Roland Co.
_v._ Walling, 326 U.S. 657-678 (1946));

(12) employees of a window-cleaning company, the greater part of whose
work is done on the windows of industrial plants of producers of goods
for interstate commerce (Martino _v._ Michigan Window Cleaning Company,
327 U.S. 173-178 (1946));

(13) mechanics engaged in servicing and maintaining equipment of a motor
transportation company which is engaged in interstate commerce (Boutell
_v._ Walling, 327 U.S. 463 (1946)). Nor does the maxim "_de minimis_"
apply to the act. Hence the publishers of a daily newspaper only about
one half of one per cent of wh