The Atmospheric Railway 1843 -1854
The Neighbourhood of Dublin
The great success of the Dublin and Kingstown Railway, constructed in the years 1832-4, naturally resulted in numerous schemes for other railways all over the country. That which was considered to have the first claim, however, was for the extension of the Kingstown line southward towards Bray, and this would no doubt have been carried out, but for a new system of propulsion championed by the eminent engineer Brunel, known as the Atmospheric system, in which the engine supplying the power was stationary, and the train was drawn along by the suction of a plug or piston through a tube. This system was emphatically denounced and opposed by Stephenson, the great locomotive engineer, and for a time, public opinion was much divided and puzzled by the claims of the rival systems as advocated by their two great protagonists. Ultimately, James Pim, an eminent Dublin citizen of his day, wrote a pamphlet or petition in favour of the Atmospheric system which attracted such widespread attention and support, that commissioners were appointed to inquire into and report upon it. Their report having been favourable, a loan of £25, 000 was granted for the construction of a line to Dalkey, and land for the purpose was granted by the Harbour Commissioners, adjoining their line, locally known as "The Metals," for the haulage of granite from the Dalkey quarries for the Kingstown harbour piers. The working of the line was entrusted to the Dublin and Kingstown Railway Company, and it was opened for traffic in July, 1844, after it had been running experimentally for some months previously
The following is the plan on which the system was worked, and which had been tried for short distances in England. A pipe, 15 inches in diameter was laid between and on a level with the rails, and the air in this was exhausted from one end by a powerful steam-driven air pump, forcing a travelling piston along the tube by the pressure of the atmosphere. A rod or plate connecting the piston with the train, travelled along the pipe in a slit covered with soft leather flaps which opened and closed again as the rod passed along. The piston consisted of an airtight plug connected with and followed by a metal framework seven yards long, closely fitting but not airtight in the tube, to give stability of direction to the plug, and the rod connecting the piston with the train was well behind the front of the piston, by which arrangement, leakage was reduced to a minimum as the train passed along. The slit, as stated, was covered by leather flaps, which were greased with a composition of wax and tallow, and after this slit was opened by the connecting rod, a wheel behind it attached to the train, pressed it down again, while a copper heater following, filled with burning charcoal, was supposed to melt the composition and seal it down again. This latter contrivance, however, proved ineffective, as its rate of movement, 30 to 40 miles an hour, was entirely too rapid to enable it to melt the composition.
In time it was found necessary to supplement these arrangements by employing an attendant to follow each train and to press down and further grease the leather flaps.
Notwithstanding the mechanical disadvantages of the atmospheric system, the line seems to have worked well, continuing in use for nearly eleven years, and all experts seem agreed that the workmanship and execution of everything connected with it were of the highest class.
The engine house where the great air pump was worked by a steam engine, stood on Atmospheric Road, on the site now occupied by the house called "The Bungalow." With its tall chimney it formed a conspicuous object in the then sparsely inhabited neighbourhood, and the great fly-wheel possessed a fascinating interest for the juvenile residents. A small reservoir adjoining, supplied water for the engine, and immediately beyond this was the old Dalkey station, about five minutes walk from the village. Portions of the masonry connected with the engine house may still be seen on the railway cutting, adjoining the site.
For a short period prior to the suppression of the atmospheric by the locomotive system on this line, both systems worked concurrently, and at one stage of the transition period when some difficulties arose which necessitated the stopping of all traffic, John Wilson, the well-known owner of the "Favourite" fleet of Dublin omnibuses came to the rescue, and supplied the missing link between Dublin and Dalkey.
In appearance the carriages were similar to those on the Kingstown railway at the time, and the front one, which carried the connection, was called the piston carriage. The fares were: 1d 3rd class and 2d 2nd class - there was no first. The line commenced immediately beyond Kingstown station, and passengers walked from one platform to the other. The speed was pretty much the same as the locomotive driven trains from 30 to 40 miles an hour.
The pipe ended about 100 yards before reaching Dalkey, the momentum carrying the train into the station, and a look-out man at the power house stopped the pumping engine when he saw or heard the train approaching. The pressure was shown at the power house by a special barometer in connection with the tube
As the line was uphill the whole way to Dalkey, the return journey was performed by gravity, and before leaving Dalkey station, an attendant lifted the piston by means of a lever, and hooked it up under the train, so as to run clear of the tube.
On one occasion a serious explosion occurred at the power or engine house, which so deranged the machinery, that the trains had to submit to the indignity of being towed along by one of their hated rivals, a locomotive engine.
The Atmospheric Railway was a great attraction in the district, and brought numerous visitors there, besides which engineering experts were sent by many foreign governments to inspect and report on the workings of the system. In fact, during the period of the railway mania, the attention of half Europe was focussed on this little line, descriptions of it appeared in many foreign papers and magazines, and "The Illustrated London New" of the 6th January, 1844, contains an illustrated article on the subject.
The line, which was exactly 9,200 feet in length, was identical nearly the whole way with the course of the modern railway, but at Castlepark Road, the old Atmospheric track diverges from and forms a loop with the modern line, and the old granite bridge which crossed it may still be seem adjoining the bridge over the railway.
An experimental telegraph line for signalling purposes was carried on supports projecting from the embankment along the line, but it is stated to have been a failure.
The principal cause which led to the suppression of the atmospheric by the locomotive system was the difficulty of keeping the leather flaps air-tight, which proved greater than was anticipated, and added considerably to the cost of working, as attendants had to be employed for the duty. Trouble was also caused by rats gnawing the leather for the sake of the grease.
There are many still living who have travelled on this interesting little line, and its memory is perpetuated in the title of "Atmospheric Road" which adjoins the cutting from Castlepark Road to Barnhill Road.
For detailed technical information on this subject, see "Stephenson on the Atmospheric Railway system, 1844"; "Mallet, Kingstown and Dalkey Atmospheric Railway, 1844"; and "Bergin, Atmospheric Railway, 1843" - all in the National Library, Dublin.