HERBERT R. O'CONOR, GOVERNOR. 501

estate, joint stock company, insurance company or corpora-
tion, whether domestic or foreign, or the receiver, trustee in
bankruptcy, trustee or successor thereof, or the legal repre-
sentative of a deceased person, which has or subsequent to
January 1, 1935, had in its employ one or more individuals
performing services for it within this State. All individuals
performing services within this State for any employing unit
which maintains two or more separate establishments within
the State shall be deemed to be employed by a single employ-
ing unit for all the purposes of this Act. Whenever any em-
ploying unit contracts with or has under it any contractor or
sub-contractor for any employment which is part of its usual
trade, occupation, profession, or business, unless the employ-
ing unit as well as each such contractor or sub-contractor is an
employer by reason of Section 19 (f) or Section 8 (c) of this
Act, the employing unit shall for all the purposes of this Act
be deemed to employ each individual in the employ of each
such contractor or sub-contractor for each day during which
such individual is engaged in performing such employment;
except that each such contractor or sub-contractor who is an
employer by reason of Section 19 (f) or Section 8 (c) of this
Act shall alone be liable for the contributions measured by
wages payable to individuals in his employ, and except that
any employing unit who shall become liable for and pay con-
tributions with respect to individuals in the employ of any
such contractor or sub-contractor who is not an employer by
reason of Section 19 (f) or Section 8 (c) of this Act, may
recover the same from such contractor or sub-contractor. Each
individual employed to perform or to assist in performing the
work of any agent or employee of an employing unit shall be
deemed to be employed by such employing unit for all the
purposes of this Act, whether such individual was hired or
paid directly by such employing unit or by such agent or em-
ployees, provided the employing unit had actual or construc-
tive knowledge of the employment.

(f) "Employer" means: (1) With respect to the calendar years
1936 and 1937, any employing unit which in each of 20 differ-
ent weeks within either the current or the preceding calendar
year (whether or not such weeks are or were consecutive) has
or had in employment, eight or more individuals (not neces-
sarily simultaneously and irrespective of whether the same
individuals are or were employed in each such week), and,
with respect to the calendar year 1938 and any calendar year
thereafter, any employing unit which in each of 20 different
weeks within either the current or preceding calendar year
(whether or not such weeks are or were consecutive) has or
had in employment four or more individuals (not necessarily