ON THE CONSTRUCTION OF THE HIGHLAND RAILWAY. 151 



On the Construction and Works of the Highland Railway. By Joseph 

 Mitchell^ F.R.S.E., F.G.S., C.E., and Member of the Institution 

 of Civil Engineers. 



This title represents the iinion of several Coropanies in the north of 

 Scotland, amalgamated three years ago under the name of the Highland 

 Eailway Company. The works consist of a main line from a point near 

 Perth, extending northward 117 miles to the town of Forres, and a base- 

 line running nearly at right angles to the other, extending westwards from 

 the town of Keith by Elgin and Forres along the shores of the Moray Firth 

 to Inverness, and thence along the Beauly, Dingwall, and Dornoch Firths, 

 northwards to Bonar Bridge, measuring from Keith to Inverness 55 miles, 

 and from Inverness to Bonar Bridge 58 miles, and making together a base- 

 line of 113 miles. These railways traverse the northern part of Perthshire, 

 and are the main lines of communication through part of Banffshire and 

 the counties of Inverness, Nairn, Moray, and Koss, the whole including three 

 branches — two to the ports of Burghead and Findhorn in Morayshire, and the 

 other to the village of Aberieldy in Perthshii-e — and extending to 24G miles 

 length. 



The countiy is fertile and comparatively flat for a distance of about 40 

 mUes north of Perth, and also along the shores of the Moray, Dingwall, and 

 Dornoch Firths ; but between Perthshire and Morayshire the line crosses two 

 ranges of the Grampian Mountains, the one separating the vaUey of the Tay 

 from that of the Spcy, and the northern range separating the Spey from the 

 valley of the Findhorn. 



The large rivers which chain these mountain -regions debouch into the Tay, 

 the Moray, the Dingwall, and the Dornoch Firths, and as the railway in 

 most cases crosses these rivers near the sea, bridges of considerable magnitude 

 Avere required. Besides the crossing of these rivers, other difficulties of a 

 formidable character arose in crossing the mountains at so great an eleva- 

 tion, and in passing the rocky and precipitous defiles through which portions 

 of the line had to run. 



The northern counties traversed by these railways, except along the shores of 

 the Firths, are chiefly pastoral, exporting large numbers of sheep and cattle^ 



The fisheries also are on an extensive scale ; besides the salmon fisheries 

 in the rivers, the annual take of white fish in the Moray Firth amounts to 

 about 60,000 tons. 



The object of the promoters, therefore, was to sweep the fertile shores of 

 the Moray Firth, ancl to send the produce of the country by the most direct 

 route to Perth, across the mountains, thus saving a detour by Aberdeen of 

 nearly 60 miles. In laying out the main line and crossing the Grampians 

 between Perth and Forres, long and steep inclines could not be avoided, but 

 there is no steeper gradient than 1 in 70 throughout. The line to Blair, 

 36 miles fi-om Perth, rises only 443 feet above the level of the sea, but from 

 Blair to the summit of the southern range of the Grampians, a distance of 17 

 miles, the line rises 1045 feet, making the extreme summit 1488 feet above 

 the sea. In this distance there are gradients for 10 continuous miles of 1 

 in 72 and 1 in 70, and in the remainiag 7 miles the inclines vary from 1 in 

 78 to 1 in 110. After passing this summit the line descends into the vaUey 

 of the Spey, falling 747 feet in 18 miles, the steepest gradient being 1 in 80. 

 On crossing the Spey, the line is comparatively level for a distance of 24 miles, 

 when it again ascends by gradients of 1 in 84, 80, and 100, in order to pass 

 the northern ridge which separates the vaUey of the Spey from that of the 



