The reference that I had was in an early machinists handbook from
pre-World War times.  I've seen Hoyt metal mentioned in other early
books and it was discussed in context with die-casting, which, I gather
from the reading, was a fairly recent development at the time of
publication of the book.

In another machinist handbook from circa 1916-1917 there was mention of
Hoyt metal, "sometimes erroneously called 'white' metal."  I don't who
Hoyt was or what his actual contribution to the die casting process
was.

Unfortunately, most of my library, including all of my early book
collection was destroyed when my house was burned down in 1982 so I'm
not able to copy and send you substantiation of what I read.

I recall that once when talking with an old-time machinist in Jackson
one day he mentioned "white" metal and when I asked him if he meant
"Hoyt" metal he said, "Yeah, I know that."

For what it's worth

Hal Davis