cap, 1] THE COMMONWEALTH OF AUSTRALIA 861 
held that the proceedings must be of a judicial character and 
that the arbitrator must not legislate. With regard to the 
provisions of s. 38 of the Act relating to the common rule 
which purported to authorize the Court to declare that any 
conditions of employment determined by an award should 
be a common rule of an industry, and of s. 39, which provided 
that a state law or an award should yield to an award by 
a Court, he pointed out that the second was ultra vires, 
and with regard to the first, while not deciding, as it was 
annecessary for the purposes of the case, he assumed that 
the provisions objected to were ulira vires. But assuming 
that these provisions were ulira vires, he still thought that 
they were severable from the other provisions of the Act. 
It had been contended on the strength of decisions of the 
Supreme Court of the United States that if the Court, on 
a consideration of the whole statute and rejecting the part 
held to be ultra vires, were unable to say that the Legislature 
would have adopted the rest without them, the whole statute 
must be held invalid. But this test he thought inaccurate. 
What a man would have done in a state of fact which never 
existed was a matter of mere speculation, which a man could 
not certainly answer for himself, much less for another. 
The safer test was whether the statute with the invalid 
portions omitted would be substantially a different law as 
to the subject-matter dealt with by what remained from 
what it would be with the omitted portions forming part 
of it. On the whole he was unable to say that the Act, 
with the alleged invalid provisions omitted, was substantially 
so different a law as to what was left from what it would be 
with those provisions included that the Court would by sub- 
stantiating the validity of what was left be making a law 
which the Parliament did not make. He proceeded, there- 
fore, to uphold the validity of the determination in the 
actual case, subject to certain qualifications which are not 
material to the question at issue. 
Barton J.2 agreed that arbitration did not include a power 
* As decided in 10 C. L. R. 266. 
11 C. L. R. 1, at pp. 34 seq. See also pp. 320-5.