By the Company's Act statutory power is given which pro tanto
modifies the otherwise exclusive authority of the Council. It is the
extent of that modification which, in my opinion, measures the
Company's right to place and to maintain its gas mains in the public
streets. To assume, first, an absolute right in the Company as if
it were a common law right, and then to demand of the Corporation
a strict justification or excuse for interference as if its powers were
an invasion of an ordinary common law right, is an inverse process, and
I reject it. Indeed, sec. 83 of the Corporation's Act of 1842 makes
it punishable for any person to break up the streets. The Act
16 Vict. No. 38, sec. 2, is permissive to the Council, but because
there is no exclusive provision it is only material, if at all, by
authorizing specifically the making of drains and watercourses as
part of a scheme including private property. Clearly, then, without
special statutory authority the Company would not merely be
committing a common law nuisance by breaking up the roadway
and putting down the gas main, but it would have brought itself
directly within the statutory prohibitions of the Corporation Act
6 Viet. No. 7, The Corporation, in making the silt pit as part of the
drainage system of a public street, was exercising statutory
diseretionary powers and as a public duty, because once the Council
thought it " proper and necessary " it was " requited " (sec. 82) to
do it. For that reason the provision is " imperative " in the sense
used by Lord Watson for the Privy Council in Canadian Pacific
Railway y. Parke (1). Speaking of a person authorized, Lord
Watson says "so long as he is not convicted of negligence " he is
not liable for damages. This would, in itself, raise a very formidable
barrier to the appellant's argument as to onus of proof, even if the
injury were in respect of a primary common law right; a fortiori
when, as here, it is of the nature I have stated. In a case depending
on violation of a common law right, Great Central Railway Co. v.