Can identification method and apparatus
 A method of forming identification markings on a thin walled can, includes the steps: PA0 (a) forming the can bottom wall to have outwardly concave shape, PA0 (b) providing a punch and forming discrete projections thereon to be separated from one another, PA0 (c) and displacing the punch relatively toward the can concave bottom wall to cause the projections to penetrate the wall to depths less than the wall thickness, thereby to form discrete and separate indentations in the can wall, the identations defining at least one recognizable alphanumeric character, and PA0 (d) relatively retracting the punch away from the can bottom wall. 
B B
B44B B44B
inventional inventional
James D.
Anderson