These are rather nice blocks, but I didn't know how nice, how big, or what they were when I bought them. Mostly just that they were made by the Embossing Company of Albany, New York, and looked like fun.
A little Googling and I turned up this image of the box lid on the ever-interesting Architectoys.com web site and learned they were "Stabuilt Blocks" from circa 1917. In an odd coincidence, I had lost an eBay auction a couple of hours earlier, thought that the winning bidder 's name "George Wetzel" looked familiar, and had had Google lead me to the same familiar web site -- one I have ended up at many times while researching or just "poking around." I am hoping he will give me permission to keep using the image.
One of the things that attracted me to the set was the inclusion of several loose pages of designs from the manual. They looked like the kinds of things I would enjoy building, and indeed I have.
The boat, by the way, is about 24" long.
My set is missing many of the connecting dowels (which I will replicate in due time). In the meantime, most of the blocks shown here are unconnected, leaning more on the traditions of classic block play.