“There was some discussion as to the propriety of making the requirements of this clause compulsory instead of merely permissive. After the fullest consideration however, it was thought essential, with the view of avoiding discussions in vestries, and especially with the view of counteracting the underhand and secret influence which the gas companies exert in many vestries and district boards, to make the clause compulsory. There are many instances on record, where powers are given to local authorities, and yet these powers, although highly important to the public interests, have never hitherto been exercised. Hence an additional reason for positively requiring them to provide apparatus, &c., for testing the gas, and to appoint and pay an inspector for the purpose. It is true that no time is fixed within which the apparatus is to be provided and the inspector appointed, but I apprehend it will be competent for any ratepayer to compel, by mandamus, the performance of this duty by any vestry or district board, within a reasonable time. “The second section of the clause imposes an obligation on the gas companies—namely, that each of them shall within six months erect at the prescribed distance from their works, an experimental meter and other apparatus for testing the illuminating power of the gas. “Now these two obligations, the one on the local authorities of the metropolis, and the other on the gas companies, must not be confounded, because they are perfectly distinct, and the one is not to be a substitute for the other. In the first place each local authority in the metropolis—_i.e._, each vestry and district board, about thirty-eight in number, constituted under the Metropolis Local Management Act, is to erect its own apparatus, and appoint its own inspector; and from future clauses it appears that the act contemplates a continuous and regular succession of testing by this inspector, both for purity and illuminating power. The evidence of this inspector however as to any defects in the gas, will not be conclusive until his report has been confirmed by testing the gas at the prescribed distance of 1000 yards from the works. Hence the necessity for the obligation on the company. The next clause will better explain the mode of proceeding by the inspector, whenever he finds the gas to be below the prescribed standard of illuminating power. With reference to purity there is nothing about testing for this at the distance of 1000 yards, and therefore the test for this may be made wherever the inspector pleases.