366 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1907. 
by the London and Northwestern Railway Company, which under 
an old agreement with the canal company controls the navigation. 
This map also, following the well-known map of Mr. Lionel Wells, 
makes an attempt to distinguish the canals in respect of their capacity, 
and it will be noticed what a large proportion of them are small 
waterways of less than 4 feet in depth, many being not merely shallow 
but narrow and capable of being used only by what are known as 
narrow boats.? 
Further, on this map an attempt has been made to indicate the 
effect of inequalities of level on inland navigation. In one respect 
the most satisfactory maps that have been published, so far as I 
know, giving indications under this head, are the large maps showing 
the waterways of England and Wales, of Ireland, and the Scottish 
midlands, respectively, attached to the paper “On Waterways in 
Great Britain,” read in November, 1905, by Mr. J. A. Saner, M. Inst. 
C. E., to the Institution of Civil Engineers, of which the author was 
good enough to favor me with a copy. These maps show the water- 
ways in relation to the physical features as indicated by contour 
lines and intervening coloring. It is to be regretted, however, that 
they do not give the number of locks on the different waterways, 
which the scale of the maps would have made comparatively easy. Of 
the difficulties presented by English canals the best idea may perhaps 
be obtained from the sections published in Mr. E. A. Pratt’s “ British 
Canals.” On the map now shown the number of the locks on different 
canals and waterways, or sometimes on ‘sections of canals, has been 
given in figures, but the map is on rather a small scale for that to be 
done quite satisfactorily. It will, however, at least serve to keep us 
in mind of the fact that in this respect English waterways mostly 
suffer from great drawbacks. 
It may be worth while to examine some of the more important 
canals separately with reference to this point. It will be noticed that 
there are three waterways connecting South Lancashire with the West 
Riding of Yorkshire, and, accordingly, crossing the Pennine chain; 
two of them independent canals, the third railway owned. The most 
important of these is the Leeds and Liverpool Canal, the northern- 
most of the three, which, it will be observed, has fifty-one locks on the 
one side, forty-four on the other. It has, however, the easiest route 
of the three, going through the important feature which Mr. Mac- 
kinder has well called the Aire gap, at the height of only 477 feet 
above sea level. The Rochdale Canal, the next to the south, rises 
above 500 feet, and the Huddersfield Canal reaches its summit, 656 
*The work affording the most complete information about English waterways 
under this and all other heads connected with their use is Bradshaw’s ‘“‘ Canals 
and Navigable Rivers of England and Wales,” by H. R. de Salis (London, 1904). 
