http://books.google.com/books?id=KioDAAAAMBAJ&lpg=PA168&ots=P565hMmuSh&dq=glues%20and%20hardening%20agents&pg=PA173#v=onepage&q=glues%20and%20hardening%20agents&f=false (http://books.google.com/books?id=KioDAAAAMBAJ&lpg=PA168&ots=P565hMmuSh&dq=glues%20and%20hardening%20agents&pg=PA173#v=onepage&q=glues%20and%20hardening%20agents&f=false)
I was browsing for something about glues and adhesives when I came across this paragraph blurb in the 1959 popular science magazine for measuring low currents with a snap around ammeter.
Looks like a good tip.
Come to think of this entire issue was an interesting read.