Denis:
 
Here are some references to dry or nearly dry washers that I found in my
historical NM database. I do believe the original writers were wearing at
least one pair of rosey glasses, but...
 
The Bennett Machine was reviewed in the Nov. 1, 1881 *Mining World.* It was
a portable dry-washer that worked by force of gravity and amalgamation, and
was run by a 10-horse-power engine. According to the Mining World, the
capacity of this amazing machine was 1,000 cubic yards of gravel a day! Even
better, it would run on as little as six inches of water. Numberous small
water jets passed the pay dirt over 30 amalgam plates, which caught the
precious metal. Cost of treatment was ten cents a yard. On 2-20-1884, p. 3.
the *Albuquerque Daily Democrat* remarked that it hoped that D. W.
Longwill's proposed new $75,000 plant at Cerrillos, NM, would be more
successful than the Bennett amalgamator machine.
 
Other machines mentioned during that same period, but not fully described
were the Hall dry-wash machine and the Jordan machine, which must have at
least vaguely worked as W. George Day ordered a second one.
 
The *Mining World*, which can be obtained on microfilm, is a never-ending
source of detailed, if none-too-exact, information and amusement.
 
*Abert's New Mexico Report, 1846-47,* Reprint--Albuquerque: Horn Wallace,
1962, pp. 33-34 contains an excellent description of an arrastra.
 
Hope this info. is helpful.  JC Sanchez
 
Denis Gojak wrote:
 
> Dear all Hist Arch readers
>
> I am seeking comparative information on technologies used in arid gold
> field situations to extract gold from alluvial deposits without using
> water, especially late 19th century to about WWII.
>
> Denis Gojak
> Historical Archaeologist
> New South Wales National Parks and Wildlife Service
> Australia