To make a long story short, found these while looking for something else. I can remember getting these in a pile from an auction. but how they found there way into the smithy good scrap steel bucket has me baffled. I believe they are new, the drive end looks to me like a #2 morse, but those pesky tapers can fool you specially the smaller ones. They were not rusty the last time I saw them!  Edit and of course I did not find what I was looking for!!!!

Huh, never seen a drill bit like those before

Hello, Oldgoaly. At first I thought of using those for drilling glass, or ceramic tile. I did a little digging, and came up with the following;   
 

Watts Brothers Tool Works is a tool manufacturer located in Wilmerding, Pennsylvania. They are known for manufacturing drill bits that can drill square holes,[1][2] including blind holes which cannot be made with other methods such as broaching. The Harry Watts square drill bit is based on a Reuleaux triangle shape, and is used together with a guide and a special chuck to make a square hole.[3][4] Similarly, the company also manufactures drill bits for other angular holes such as pentagons and hexagons. Regards, Lou  Just a guess!!!!!!!!!!

Good video of triangular bit in action...

http://www.mikesenese.com/DOIT/2011/10/drilling-square-holes-with-a-reuleaux-triangle/

That is cool.  I am always impressed with the thinking it takes to come up with something like this.  What is it they say about ingenuity being the mother of invention?

Quote from: Catch22! on January 29, 2017, 11:22:51 PM
That is cool.  I am always impressed with the thinking it takes to come up with something like this.  What is it they say about ingenuity being the mother of invention?

"Necessity is the mother of invention"

Those bits are not Reuleaux triangular.

I saw the square hole bits, they are offset so it makes a squarish hole, the shank is centered. They also are not sharp on the sides / flutes?
Only place I can feel a sharp edge is the tips. I thought spot facing? but the angles of the tips would be odd?
Certainly not an hammer drill? no retainer they would fall out rather easily?
Wondering what metal the main part of the bit is? the taper is common steel it rusts.

Could be a scraper then...   now that i look again i don't see them curved either...   

I think the one on the right might be a machine tool.  Flat part up makes a nice point.  Ive not seen a holder for this, though.  I'm thinking lathe tool.

Chilly

the taper could very well fit the tailstock of a lathe.
the only sharp areas are the tips.

Cleaned the bits up today in some phosphoric acid. Found the name "Black Drill Co. Cleveland Ohio, patent# us2260228a
https://patents.google.com/patent/US2260288A/en?oq=2260288Granted Oct. 28th 1941
Only took a couple of years to figure it out!

I have a flyer for those type of bits somewhere.  I am out of town, but will try to remember to look for it when I get back on Friday.

Ahh, for hardened metal. Makes sense. Back in the days before carbide bits were so readily available.