Industrial smoke was apparently a sign of a strong and vibrant city a century ago. Real estate man R.L. Cate certainly played up what we’d consider pollution today in his richly illustrated ad, calling particular attention to timber, hops and wool.
(University of Oregon Libraries)
Vintage Portland 
Is that a train station with the tower on the East bank, at the south end of the picture?
Igor.
It might be, but it doesn’t look the like illustrator paid much attention to accuracy of the details. For instance, he depicts the old Oregonian Building as being near Taylor, South of Morrison, when in fact it was actually on Sixth and Alder, North of Morrison. It also looks like he may have placed the Portland Hotel on or near Burnside instead of between Yamhill and Morrison. What appears to me to be the old Chamber of Commerce building is on Yamhill in the illustration, but in reality it was on Stark between Third and Fourth Avenues.
For a Portland Realitor, R.L. Cate either didn’t know his territory well, or he neglected to proof the illustration.
This is currently known as “truth” in advertising!
This post says 1906 but the UofO entry for this publication reads: “The new age. (Portland, Or.) 1896-1905”
Can’t find this in a search there.
When this ad came out Portland was the second richest city on the west coast. Sadly now it has sunk to about fourth or fifth, maybe even lower.
We have this 1908 pana-photo of Portland in our home. The ad isn’t too far off as far as depiction…smoke and all!