THE PREHISTORIC COPPER IMPLEMENT QUESTION. 603 



tion to the two-or-three-centuries-old works of Spanish and French adventurers, 

 to whom it has been the fashion, hitherto, to attribute anything of that kind. 



The foregoing article was read at the December meeting of the Des Moines 

 Academy of Science, for criticism, suggestion, or amendment. The copper reUc 

 in question was subjected to more thorough examination with various styles of 

 magnifying glasses which were at hand — mostly pocket-instruments, such as 

 physicians usually carry for ready convenience. And the conclusion was practi- 

 cally unanimous that the ax had been made in a moli, but by the process of cold- 

 swedging a piece of native copper, and not by melting it. The rough, grainy 

 surface, that looked and felt so much like a casting, was thought to have resulted 

 from oxidation ; and the appearance of air-bubbles in the line of fracture was 

 thought to have been an original flaw in the ore. 



The next day I took the relic to Dr. E. H. Carter, Dean of the Iowa Elec- 

 tric Medical College (medical department of Drake University), and examined 

 it with a magnifying power of eight hundred diameters. Dr. Carter, who is one 

 of our Academy members, but who was not present at the meeting, first detected 

 spicules of vitreous quartz imbedded in the copper. I afterwards verified his 

 discovery, and also found several others ; they were so fine that no hand magni- 

 fier would reveal them at all, but under this high power they were as plain as 

 quarry stones ; and here was further proof that this piece of copper was pure 

 native ore, which had never been melted by man. We detected also a crease or 

 depressed wrinkle that had been produced by the compression or crowding to- 

 gether of the surface of the metal. 



Conclusio7is. — Out of all this investigation I evolve the following summary : 



1. Prof. Putnam's statements and criticisms were altogether too general — 

 were even obnoxious to his own strictures ; for he did not discriminate between 



free-hammermg and swedge hammering ox pounding, in the matter of different modes 

 by which our ancient stone-folk worked copper. And he did not discriminate 

 between molds for swedgivg into shape pieces of cold native copper, and molds for 

 casting molten copper. 



2. If Dr. Hoy reports him correctly, Mr. Conant admitted in his letter 

 more than the case required.. 



3. The evidence in regard to prehistoric furnace-work is not all in. There 

 are some " connecting links " yet to be discovered. 



4. I reverse judgment and correct my error. My copper ax was not cast 

 from melted copper, but was shaped by the process of cold-swedging in a mold 

 or matrix worked into some kind of very hard stone. 



Des Moines, Iowa, December 15, 1881. 



V— 38 



