|You can just about read this. Click for bigger.|
It's not. As the close-up image shows, there's something going on between the upper and lower bevel gears, something that includes a little gearshift similar to the one found on "Yankee" push-driven screwdrivers. But where those only have three positions -- forward, locked and reverse -- this has five.
In PLAIN, it works like any other drill.
L.H. RATCHET makes it run only counterclockwise. Turn the crank the other way and the chuck stays put.
R.H. does the opposite: The drill only turns counterclockwise.
LOCKED conveniently locks up the whole works, making loosening and tightening the chuck an easy operation.
But I skipped one. Here's the magic: select R. H. DOUBLE and it doesn't make any difference which way to turn the crank: the chuck always turns clockwise, with nary a hitch as you change the direction of the driving gear!
There doesn't seem to have been a lot of use for this functionality, but if you needed it, there were no substitutes and North Brothers Manufacturing (and later Stanley) built this one and a larger size for many years.
|A slightly wider view of the 1530|