How Your Hobby Started Part XIX

390447th Avenue, S., Seattle, Washington 98118

Mention was made in the July-August Volume 6 issue of the Gas
Engine Magazine of a rare make of engine by the Priestman & Co.
of Philadelphia, Pennsylvania and also with offices and
manufacturing plants in London, and Hull, England and Glascow.

From this article came several very informative letters from one
of our readers, Anthony Harcombe, Esq., residing in Westcott,
Surrey, England. He has a collection of expertly reclaimed antique
engines including a Priestman, a Southwell, a Richard Hornsby, a
Petters, a Fairbanks, Morse Type ‘T’ and others.

The 2 HP vertical, single cylinder Southwell is very similar to
the Fair banks Morse Type ‘T’. The difference is in the
push rod for the exhaust valve, which on the Southwell has only one
push rod. It actuates both the exhaust valve and the igniter, while
on the Type ‘T’ there is a push rod for each of these
functions. Also the Type ‘T’ has a gear driven low tension
magneto as original equipment while the Southwell is equipped with
a battery, choke coil and igniter.

As can be seen from the picture, the Southwell has a mixing
valve mounted on top of the cylinder head, with an igniter located
just below in a boss cast on the side of the cylinder. The governor
and timing gear are located outside the closed crankcase and a
rocker arm to operate the fuel pump. The fuel tank is located
between the engine mounting skids

Plainly stated on a brass plate on the side of the crankcase
hand hole plate is the fact that it was made in the U. S. A. After
correspondence with a number of the well known engine collectors in
our country, it has not been possible to trace any information
concerning the the manufacturer of these engines. Undoubtedly it
would be interesting to the readers of G.E.M. to learn more about
the Southwell engines and should anyone be able to offer additional
data, it will be gladly added in a future installment of this
story.

The other very rare engine in this Harcombe collection is the
Priestman. From the pictures it can be seen that this company built
different types in this country than those in existence now in
England. (With assistance of Dave Reed of Elsmore, Wilmington,
Delaware reproduction of pictures of the Priestman engine catalog
is shown in order that a comparison can be made of the Philadelphia
engine and the one now in Surrey).

The details of the construction and operation can also be
compared from the page of the Philadelphia catalog and Anthony
Harcombe’s letter; which is quoted here in its entirety:

Southwell 2 HP gasoline engine owned by Anthony Harcombe,
Westcott, Surrey, England. The engine was made in U. S. A.

PRIESTMAN’S OIL ENGINE

Anthony Harcombe Westcott, Surrey, England

Dear Carleton, I read with some interest, your mention, in a
previous G.E.M. of the American Priestman engine, (Vol. 6, No. 4)
because I have in my collection, what is believed to be, the only
working example of this revolutionary machine. The only other
survivor is in the Science Museum in London. They are of course the
British design. I would be very interested to hear if any American
ones still exist.

William Dent Priestman was born near Hull in Yorkshire in the
year of 1847, educated at a Quaker School at York and was
apprenticed to W. G. Armstrong & Co., later known as Armstrong
Whitworth & Co.

His father started him in business at a small foundry in Hull in
1870 where he undertook general repairs to machinery of one sort or
another.

He was a modest man but a man of great courage and perseverance.
He fought for the abolition of slavery and was the instigator of
the anti-bribery and corruption Act of Parliament. In the late
1870s he was determined to succeed where others had failed, namely
to produce an engine which would run on ‘common petroleum’
or lamp oil. Hitherto engines away from a town gas supply had to
either have expensive gas producers or be run on petroleum spirit,
the handling and storage of which was made almost impossible by
stringent safety regulations and insurance premiums.

Priestman 6 HP gasoline engine owned by Anthony Harcombe,
Westcott, Surrey, England.

After some years of patient research he succeeded in producing a
vaporizer assembly which was to be the focal point of his
successful engine.

The patent for this was drawn out in 1885, at which time Rudolf
Diesel was managing an ice works in Paris, and Herbert Ackroyd
Stuart had only just begun experiments. Production was soon under
way and the Priestman engine was exhibited at the Royal
Agricultural Show in 1888 and won medals for three years
running.

Operation of the engine was briefly as follows:–the fuel tank
cast into the engine base, was kept pressurized at 8 to 10 lbs. per
square inch by a piston pump attached to the exhaust valve push
rod. Initial air, for starting, was provided by a hand pump behind
the engine. Oil flowed via a dip pipe and a suitable lever valve,
to the heater lamp for starting, and to the spray valve in the
vaporizer. Also, via this valve air alone passed under pressure to
atomize the fuel in the sprayer. The vaporizer chamber heated at
starting by the lamp, is kept hot by the exhaust gas whilst the
engine is working.

The vaporized oil passes into the cylinder through an automatic
inlet valve and the charge is compressed and fired by a high
tension spark.

The spark was provided by a system undoubtedly designed by
French electrical engineer Eugene Eteve and was powered by a series
of Voltaic cells. The low voltage circuit was made at the firing
moment by a brass bell on the exhaust valve rod passing between two
metal tongues allowing current to flow into a buzzer and high
voltage trans former. The circuit being the same as the trembler
coil ignition being fitted to new vehicles thirty years later.

Whilst my Priestman runs very well on a car battery, the
original cells were unreliable, in constant need of attention, and
very messy. The engine was there fore converted, probably by the
makers at the turn of the century, to hot-tube ignition. The
original electric apparatus was, fortunately for me, left on
site.

No expense, nor come to that, any cast iron were spared during
the manufacture of these machines. The three horsepower engine in
1888 was quoted as weighing over twenty hundredweights. Great
simplicity of design combined with a very high standard of finish
and fitting made the Priestman engine a legend in its  own
lifetime.

Fairbanks Morse Type ‘T’ gasoline engine owned by
Anthony Harcombe, Westcott, Surrey, England.

Mr. Philip D. Priestman, President of Messers Priestman
Brothers, Hull, and son of the founder, informs me that a thousand
of these engines were made from 1888 till about 1900 when
production ceased.

Ackroyd Stuart’s patent in the skillful hands of Messers
Richard Hornsby & Sons of Grantham, was beginning to tell on
Priestman’s sales and this, coup led with the fact that their
interests were turning to dredgers and excavators which have since
made them famous, made them stop engine production.

My engine, which is about six horse power has a bore of 7?’
and a stroke of 12′, the weight being just over a ton. Engine
speed between 190 and 200 rpm.

I discovered it lurking in an old pump house not five miles from
my home and after a lot of struggling, two kind assistants and
myself armed with ropes, boards, lorries, vans, etc., managed to
get the thing home. But not before, I hasten to add, a five ton
trolley jack had been crunched, a tow rope broken, a clutch partly
incinerated and last but not least, a nose broken!

The engine is now finished, the work involved being mainly
cleaning and rust removal, a few parts only, having to be made. The
first time she was started, the procedure which should normally
take twenty minutes, took at least three quarters of an hour, but
with the aid of my wife, we won!

The chart ‘D’ on page 9 of the July-August 1971 issue
gives the only specifications available on the size of engines
built in this country by this company. Undoubtedly, they built
other sizes as indicated by the fact that a different size bore and
stroke is given in the above letter and which size is not listed in
the U. S. specifications.

Priestman 6 HP gasoline engine showing construction details,
owned by Anthony Harcombe, Westcott, Surrey, England.

System Operation

A. Oil tank filled with any ordinary high test (usually 150?
test) oil, from which oil with air under pressure is forced through
the B. Three Way Cock, and conveyed to the C. Atomizer, where the
oil is broken up into atoms and sprayed into the D. Mixer, where it
is mixed with the proper proportion of supplementary air and
sufficiently heated by the exhaust from the cylinder passing around
this chamber, from which it is drawn by suction through the Inlet
Valve I into the E. Cylinder, where it is compressed by the piston
and ignited by an electric spark passing between the points of the
F. Ignition Plug, the current for the spark being supplied from an
ordinary battery furnished with the engine, the G. Governor
controlling the supply of oil and air proportionately to the work
performed. The burnt pro ducts are then discharged through the H.
Exhaust Valve, which is actuated by a cam. The I. Inlet Valve is
directly opposite the Exhaust Valve. The J. Air Pump is used to
maintain a small pressure in the oil tank to form the spray. K.
Water Jacket Outlet.

By this system perfect combustion of oil takes place.

Priestman kerosene engine built at Philadelphia, Pennsylvania,
circa 1892.

Table of Sizes and Dimensions

Priestman kerosene engine ratings–built at Philadelphia,
Pennsylvania.

Courtesy of R. F. Somerville, 12498 14th Ave. N., Haney, British
Columbia, Canada.