Alvordton, Ohio 43501
Many of the steam traction engine manufacturers built some
compound engines. A compound engine uses the steam twice before it
is exhausted up the smokestack to increase the draft. The low
pressure cylinder generally has about double the piston area of the
high pressure cylinder, and gets its steam after it leaves the high
The tandem compound has both piston heads on the same piston
rod. In the cross-compound, the high and low pressure cylinders are
set side by side with two cranks set 90 degrees apart. The Woolf
compound was a tandem, and used by many early manufacturers who
knew their economy, but later discontinued building them due to
paying royalty on the patent, and extra cost of building.
The Woolf patent expired about 1915, and the Port Huron Engine
& Thresher Co. used their own name on the cylinder name plate.
Although they built a very good simple piston valve steam traction
engine, they realized the greater economy of their compounds. They
built only tandem compounds the last eight years building
engines.
Economy runs made at several thresher reunions about 10 years
ago, show a 40 year old 24-75 Hp. Port Huron ‘Longfellow’
developed a Hp. hour on 20.2 Lbs. of water, and evaporated 8.75
Lbs. of water per pound of coal with a 57.65 Hp. load on the Baker
Prony brake.
This economy run compares favorably with a Corliss stationary
steam engine. Compared with over a dozen other steam traction
engines including Baker Uniflows in these tests, all other engines
used an average of over 50 percent more water, and over 100 percent
more coal per horsepower hour.
In 1919, the Minneapolis Steel & Machinery Co. designed a
tandem compound steam traction engine named the ‘Twin City’
but never put it in production.
In the above mentioned Port Huron economy record, this run was
made at The National Threshers Reunion at Mont pelier, Ohio. This
engine was equipped with a crosshead pump for boiler feed, and
exhaust steam feed water heater. The firebox was equipped with a
brick arch for better combustion of fuel.
My Advance catalogue says an Advance engine will develop an Hp.
hour on 34.5 lbs. of water. At this economy test run, John Holp of
Lewisburg, Ohio beat the catalogue’s claim, and developed an
Hp. hour on 32.56 lbs. of water with his 20 Hp. Advance engine.
At the sixth and last annual Industrial Motor Contest held at
Winnipeg, Manitoba in July 1913, 14 gas tractors, and six steam
traction engines competed in their two hour economy run, hour
maximum run and plowing contests. In 1911 the J. I. Case Co. got
peeved about something, and did not have their gas tractors or
steam engines like they had in previous years, but was back in
1912, and 1913, or the last year it was held.
J. I. Case records show they built some Woolf compound steam
traction engines in 1913. Among these were two 80 Hp. Woolf
compounds No. 30375 and 30666. One of these was shipped to Winnipeg
in 1913, and entered in their contest. This Company realized the
greater economy of their 80 Hp. Woolf compound with 9′ &
13′ bore, and 11′ stroke over their 80 Hp. simple they had
there in 1912.
That 80 Hp. Woolf compound was the gold medal winner in its
class, and developed an Hp. hour on less than 27 lbs. of water.
This engine was equipped with boiler feed geared pump, and exhaust
steam feed water heater.
Here is a problem I heard at least 60 years ago when I was a
young man. It is the wheat and checkerboard problem. With a grain
of wheat placed on the first square of a checkerboard, and doubled
on each square thereafter, do you think you could pile all the
wheat on the 64 squares?
The answer is ‘No’. In fact there has never been that
much wheat grown in all the world, and probably never will be.
A grain or kernel of wheat placed on the first square of the
checkerboard, and doubled 64 times makes 9,223,372,036,854,775,808
kernels.
A bushel of good plump kernels of wheat contains about 600,000
kernels depending on the variety, and where grown. Thus these
9,223,372, 036,854,775,808 kernels divided by 600,000 kernels per
bushel makes 15,372,286,728,091 bushels.
Allowing 1500 bushels per railroad freight car, and
approximately 133 railroad cars per mile, makes 200,000 bushels per
railroad mile. This amount of wheat would make 76,861,433 miles of
R. R. cars of wheat.
As the earth is approximately 25,000 miles around at the
equator, this means over 76 million miles of loaded cars of wheat
would encircle the earth 3,074 times, and have 11,433 miles left
over.