Heinrich August Theodor Ehrhardt was born in 1840 to simple beginnings, and retired & expired(1928), in Zella Saint Blasii where in 1866 he founded his first firm which faltered. It was then that he moved to Düsseldorf where he founded the Rhinish Metal Works Rheinmetall and made many wares including corkscrews. He real 1st success was a new technique of bullet making where he fabricated 8x57I steel jacked bullets for the M88. He then went on to bigger and better bullets, and tubes, for artillery pieces in the last decade of the 19th Century. It was then that he developed his tube making process and it has been pointed out to me that the square bolt/rod in the round hole, which can be seen in the diagram between the signatures in the signature block, became his trademark. Page 5 beside "a" & "b": http://www.google.com/patents?id=S2x2AAA...;q=&f=false

I think he had the name of "Cannon King" and rivaled Krupp. In 1896 he began building autos/trucks and in 1901 he purchased the Dreyse facility in Soemmerda but post WWI his Eisenach auto works began to falter and was absorbed by BMW. Soon after he somehow lost control of Rheinmetall to a Swedish candy factory.

Kind Regards,

Raimey
rse