In the book from Hermann Stelzner there are some references to Macduffee.

The name of the inventor is often written in different ways. Stelzner calls him Macduff. He is also called McDuffie – MacDuffie – MacDuffy – Macduffie but the true name of the man was Macduffee.

Stelzner wrote:

Macduffs ADS was tested in 1915 in Long Island Sound. It was made like the “Hanseatische”from aluminum alloy and weighted about 250 kilo. The cylindrical joints mounted on ball bearings allowed movement in one direction only. They do not appear to be watertight due to the fact Macduffee implemented a waterpump in the suit. This pump was able to pump water from the leg section into the sea. The pump operated on compressed air supplied from the surface. The used air from the pump then expanded into the suit and was used by the diver for breathing. ( Robert H. Davis Stated the pump was driven by electricity) The suit was equipped with a 12 section-gripper mounted on one arm and a electric light on the other arm. Also a hook is seen on a picture. Macduffee’s suit reached 65 meters of waterdepth in 1915!

Gary L. Harris wrote in his book Iron Suit:

Credit for constructing the first suit to utilize ball bearings as the medium to provide movement to a joint and also to act as the load-bearing surface must go to a Mr. Mac Duff­ie,  who tested his formidable-looking A.D.S. to a depth of 214 feet in Long Island Sound, New York. MacDuffie’s suit resembles a science fiction robot more than an A.D.S.