Any wooden window frame with a single glass is easy to turn into a double, having received a kind of glazing is not worse than common now brand.
This will require a brace or composite rod-the glass bead and a slightly larger format than is setup in the window so that you can lay on the frame and press with rail, bothering and seal with a rubber strip or putty.
Recommend to read
TRACTOR YOUR REPRESENTATION
"Mini tractor, description and sketches of which were published in No. 3 of the journal this year, I really liked it. As, apparently, the other readers of the "M-K", there was a desire...
ON THE WAVES – “MOTH”
Ultralight Dinghy international class "Moth" "the Moth" (Fig. 1, 2) simple in design, convenient in construction and possesses all the essential qualities of sports ships - fast,...