Mr. Eisenberg. You say these are particularly strong marks?
Mr. Cunningham. These are very, very, good marks.
Mr. Eisenberg. Now, these marks are on the brass, so to speak, of the cartridge case, rather than in the primer?
Mr. Cunningham. Yes; that is correct. Actually, it is brass, it is nickelplated brass.
Mr. Eisenberg. Is that unusual, to be able to pick up such strong marks in the brass as opposed to the primer of the cartridge case?
Mr. Cunningham. It is not really unusual; no. It depends upon the particular weapon.
Mr. Eisenberg. Did you also examine the microscopic markings on the primer?
Mr. Cunningham. I did.
Mr. Eisenberg. And you found what?
Mr. Cunningham. I could identify the weapon on the basis of the imperfections, individual characteristic marks, in the firing-pin impression.