256 DISCUSSION ON 
this where parallel to the coast for its whole length ran a moun- 
tain barrier from two thousand to four thousand feet in height. 
As bearing on this part of the subject, he would like to make a 
few remarks with regard to certain types of engines, but not pre- 
tending to be a locomotive engineer he submitted them with all 
modesty. The Fairlie Engine which he first saw running on the 
Festiniog line in North Wales, was designed for the double purpose 
of getting flexibility, for working sharp curves, and of utilising 
the whole weight of the locomotive for adhesion. The first of this 
type looked like two engines back to back, and really consisted of 
two boilers rigidly connected, placed on two bogies provided with 
separate pairs of cylinders. The improved Fairlie had one boiler 
and fire box, but the use of the bogies was continued. There was 
a serious difficulty in connection with all these engines, viz., that 
of keeping its steam connections tight. High pressure steam had 
to be conveyed down through the centre pivot to the cylinder, 
and this was a source of great trouble, therefore it was quite 
possible that as Mr. Thow said, engines of this type had often 
been consigned to the scrap heap. There was another type of 
engine however which seemed more promising, and was doing 
good work on the St. Gothard, Central Swiss, and other lines, 
and this was the Mallet type. In this the high pressure cylinders 
with the main framing were made with a fixed connection to the 
boiler, while the low pressure cylinders which were placed at the 
front end on a bogie were made to swivel under the boiler. The 
steam pipes were said to give no trouble, flexible connections were 
only required to convey steam of reduced pressure to the low 
pressure cylinder, and to take the exhaust steam to the blast pipes. 
On the Central Swiss line tank locomotives of sixty tons distri- 
buted on four axles in two pairs were used. On the St. Gothard 
line locomotives of eighty-five tons on six axles in two sets of 
three were being run. These must be very powerful machines, 
as all the weight was available for adhesion, instead of from only 
fifty-five to sixty per cent. as in the cases of the usual type of 
engines, and they must possess great flexibility. It followed that 
