Although not downloadable, these old magazines are easily readable online thanks to hi-res scans. And they’re always interesting.
The Google scans are complete and in full color – even the ads are there. Indices of most of the individual issues contain hyperlinks to feature articles making it unnecessay to scroll through numerous pages to get to one.
Also, each magazine is text searchable so you can search through the issues by keyword. To search for a keyword across the entire archive, use Google Books Advanced Search as it now includes these magazines in the search results – just type “Popular Science” into the Title field.
Here they are from 1910-2000…plus 1870! (You may need to scroll down a bit to see the magazines, grouped by decade).
Other old pubs now in the public domain can be found here.