Welcome to QB.
It appears you have what is considered a Davis underfeed badged machine. It is listed as a badge name on the list found a t
http://www.needlebar.org/main/makers...vis/index.html Alliance was also used on National machines, but since your belt pulley is on the outside of the hand wheel, it is a Davis. I'm going to guess that it could have been made between 1903 and 1907.
There is some good info on this page about Davis machines
http://needlebar.org/nbwiki/index.php/Davis Hopefully, Jon will be along as he knows these machines. He will also be able to tell you which needles it would use. I know many of these early Davis machines took what is called a 20x1 which is longer than the needles used on modern domestic machines.
It looks like it will clean up nicely. Most recommend just wiping the machine with sewing machine oil. If you are comfortable removing the metal pieces, they can removed to clean and polish.
Have fun with your 'new' treadle.
Janey - Neat people never make the exciting discoveries I do.
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