NATURE 
nos 
THURSDAY, JUNE 29, 1899. 
PETTIGREW ON THE LOCOMOTIVE. 
A Manual of Locomotive Engineering. By William 
Frank Pettigrew, M.Inst.C.E.; with a selection of 
American and Continental Engines, by Albert F. 
Ravenshear, B.Sc., Whit. Sch. Pp. 430. (London: 
Charles Griffin and Co., Ltd., 1899.) 
T is with much pleasure we welcome this valuable 
addition to the literature of locomotive engineering 
—a subject seldom dealt with in text-books, and one 
which depends more on the results of experience than on 
theory as usually set forth in our technical schools. An 
author, therefore, in a position to deal with the subject 
in a satisfactory manner must of necessity have had a 
railway experience of no ordinary kind. In fact he must 
have gone through the mill in the form of the shops, 
works-management, and finally as locomotive superin- 
tendent. The author of this volume fills these require- 
ments exactly, consequently we are not disappointed with 
his work. 
In a volume consisting of about 400 pages we find the 
subject carefully treated, and divided into twenty-two 
chapters with three appendices. To commence with, we 
naturally find the pioneer forms of locomotives historically 
dealt with, and this is as it should be from the student’s 
point of view ; the credit, however, for earlier successes 
does not always appear to be given to the proper parties. 
The “ Rocket,” for instance, was a success mainly because 
of the multitubular boiler patented by William Henry 
James, and adopted by Stephenson in consideration of 
one-fourth share of the patent obtained by Losh and 
Stephenson for locomotive engines. The progress of 
earlier locomotives in the United States is also described 
—a very interesting subject when one remembers that 
“Old Iron Sides” was built by W. Baldwin in 1832, this 
maker being represented to-day by the eminent firm of 
the same name in Philadelphia. 
On the subject of modern simple locomotives the 
author has a wealth of material at hand, that is to say, 
on single expansion engines. In Chapter ii., dealing 
with this branch of the work, we find a cursory definition 
of wheel-base, engine power, tractive force, boiler power, 
&c. (all of which are exhaustively treated later on in the 
work), after which very: full and excellent descriptions of 
modern practice are given. The famous “Dunalastair” of 
the Caledonian Railway is mentioned ; but more should 
have been said of this engine, for Mr. J. F. McIntosh, 
the able locomotive superintendent of that railway, is 
certainly the prophet of the big boiler in this country, 
and deserves mention for this reason. Other Scotch 
engines are described, including those of the Highland 
Railway, the illustrations of which do not include the 
louvres in the chimneys, “a fatak oversight.” As an 
example of the older practice on the Manchester, 
Sheffield and Lincolnshire Railway, we find Mr. Charles 
Sacre’s single express engine ; we should have preferred 
the double-framed four-coupled bogie as a record of this 
eminent locomotive engineer. But why does the author 
omit the present practice on the Manchester, Sheffield 
NO. 1548, VOL. 60] 
and Lincolnshire, or rather the Great Central Railway, 
an example of which would have been interesting ? 
Chapter ili. deals with compound locomotives, and 
very fully does the author describe the various systems 
in vogue. Here this type of locomotive is uncommon, 
except on the North-Western Railway, where the Webb 
system is in use. Many experiments have been made on 
different railroads, but nearly all have returned to the 
simple type for express work, although for heavy goods 
traffic the Worsdell system is in use on the North-Eastern 
Railway. 
On primary considerations of locomotive design we 
find much useful information, more particularly on train 
resistance, the author maintaining that the older formule 
are not sufficiently accurate, due to various causes, and 
proposes one which agrees fairly with practice, viz. 
R =9+ 007 V2, where Ris the resistance in pounds per 
ton,and V the speedin miles per hour. On the question 
of proportionate heating surface the author gives mini- 
mum values, and goes on to say, get as much as the 
design will allow. This is no doubt the right view to 
take, and locomotive engineers in this country are 
waking up to the fact that the bigger the boiler the 
more satisfactory the engine. 
The author having been the works manager in the 
Nine Elms Works of the London and South-Western 
Railway Company for many years, one naturally expects 
to find all the detailed descriptions of parts of a loco- 
motive very practical and concise. In Chapter v., deal- 
ing with cylinders and their parts, this expectation is 
fulfilled. A useful addition would be to add a simple 
test for cylinder metal, such as a tensile test of, say, 
II tons per square inch, or the regular shearing test of 
a 2-inch by I-inch bar on supports 3 feet apart, to deflect 
three-tenths of an inch with a breaking load of not less 
than 35 cwt. 
The conical form of piston-head shown in Fig. 69 was 
adopted by the late Mr. Stroudley to enable him to get 
as long a connecting rod as possible, and was usually 
made of gun-metal for the express engines. Many piston- 
heads are running made of wrought iron, a fact which 
the author fails to mention. 
The descriptions of the arrangement of single and 
double slide bars are good, but we fail to read that the 
arrangement with four bars in Fig. 81 is the best when 
considered from the standpoint of weight of moving 
parts and balancing them. Further on, our author deals 
with connecting and coupling rods of various designs. 
Generally we find very little information as to the 
material used for these important details, and where 
steel is mentioned no tensile tests are given. 
Chapter ix. deals with the important question of 
balancing the moving parts of a locomotive when in 
motion, and we must cordially congratulate Mr. Pettigrew 
on the very clear manner he has handled this important 
subject. The examples given are clear, and are worked 
out without unnecessary use of higher mathematics. 
Valve gear, as dealt with in Chapter x., is of a purely 
descriptive nature, and includes the usual types. The 
Morton gear might have been included as a curiosity, as 
a goods engine has been satisfactorily running for some 
years on the North British Railway fitted with it. Of 
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