From Canadian Electrical News Jan 1900.
The same advertisement first appeared in the Dec 1896 issue and appeared every subsequent issue (monthly) until Jan 1907.
Two additional half-page advertisements appeared in the Jan 1900 issue: [id=488729548] [id=488729566]
A three-page article on Ness, McLaren & Bate appeared in the Dec 1898 issue: [id=410535058]
The one and only known insulator with the Ness, McLaren & Bate embossing is shown here: [id=384555035]