I am building BG's Beck-type device, and the pictures don't show what the electrodes are made of. Just the bare copper wire wrapped with thread / cotton?...
if you don't want to take in copper ions, the get stainless steel cotter pins (home depot). or better yet for purists, use pure silver wire like 10 or 12...
That was good advice. I also use silver electrodes for the same reasons. Paul ... cotter ... like 10 ... solder, ... should be ... the current ... you use, ......
From what I've been able to dig up in my research, stainless steal is preferable for use as blood electrifier electrodes over 99.99 fine silver. Never use...