LIGHT RAILWAYS FOR NEW SOUTH WALES. 61 
dulating country only, and where either no large river bridges 
occur or, where they do, existing road bridges can be availed of 
without serious additional expense. Secondly, those lines which 
are entirely or chiefly on the surface, such as in most of the 
Riverina and western plains. 
Now as to Class 1. The question of curves is very important, 
and the probability is, from what has been already said, that if 
the locomotive designers meet us, nearly half of the earthwork 
and one quarter to one-third of the culvert work might thus be 
saved ; items which form, in many of this class of line, a large 
proportion of the total cost. As to the practicability of sharp 
curves on the standard guage, the following instances may be 
quoted. In Mr. Mosse’s paper ‘“ Minutes of Proceedings Institu- 
tion of Civil Engineers, Vol. Lxxxv.,” it is stated that “In 
America, with a gauge of four feet eight and a-half inches, curves 
of from three hundred and thirty to four hundred feet radius” (five 
to six chains) “‘are traversed by four wheel coupled engines having 
a wheel base of six or six and a half feet,” and he states that, on 
the Nana Oya extension of the Ceylon railway, gauge five feet 
six inches... a large portion of the curves vary from five to 
eight chains radii, and are worked by engines having six wheels 
coupled four feet five inchesin diameter with a wheel base of nine 
feet six inches, but as the leading drivers are flangeless the fixed 
wheel base is four feet five inches. The bogie has however a 
wheel base of six feet. The resident engineer reports that these 
engines work remarkably well, with practically no flange wear ; 
they are a perfect success for working on five chain curves. In 
the same volume, in Mr. Gordon’s paper, Forney’s type of engine 
is described as having four coupled drivers forty-two inches 
diameter, working round curves of ninety feet, or less than one 
and a-half chain radius, on the New York Elevated (standard 
gauge) Railway, and also as much used on suburban lines in the 
United States. The following is quoted from the same authority. 
‘The most eminent and experienced American engineers however 
attach more importance to the free use of curvature even of great 
