Sunday, November 20, 2016

Thomas Telford's report - canals unbuilt

In the immediate aftermath of the Jacobite rebellion of 1745/46, Government would, were it possible, have cheerfully transported every single Highlander abroad. But 50 years later, when the clansmen had transformed themselves into very useful Imperial cannon fodder, the powers that be were getting distinctly alarmed at the rate of emigration from the Highlands & Islands.

Thomas Telford 1757-1834






















In July 1802, the Treasury wrote to the civil engineer Thomas Telford - best known, perhaps, for the Menai Suspension Bridge and Edinburgh's Dean Bridge - seeking his views on the matter. He was forthright in his reply:- 

I shall not encroach upon Your Lordships’ Time by investigating all the remote or unimportant collateral Causes of Emigration, but shall proceed to that which I consider to be the most powerful in its present Operation; and that is, converting large Districts of the Country into extensive Sheepwalks.  

Responding to what might done about this, Telford was more diffident. It wasn't the done thing in these days to tell landlowners what they could or couldn't do with their property and in any event, Telford thought, the current mania for sheep farming was a bubble: the market would soon be saturated and a more balanced and labour intensive kind of mixed farming involving sheep on the uplands and cattle on the lowgrounds of smaller farms of the type found and admired by Telford on the north side of Loch Tay would emerge in its place. (He was wrong about that, sadly: when the sheep bubble burst several decades later, it was replaced by deer-stalking.)


Where Telford felt himself on safer ground was in recommending that, if Government were disposed to embark on a programme of public works, now would be the time to do it in order to employ the displaced tenantry and allow them to build a little capital with which to branch out into non-agricultural industries at home rather than emigrate. Foremost among the Government's hopes for diversifying the Highland economy was the under developed west coast herring fishery. This had a been a bit of a holy grail to the Scottish authorities for nearly two centuries so prominent among Telford's recommendations was construction of the Caledonian Canal in order (amongst other benefits) that east coast fishing boats might reach the west coast without the hazard of a passage through the Pentland Firth.

Less well known than the canal, Telford also recommended the construction of roads and bridges in the Highlands at the joint expense of Government and the landowners through whose estates they would pass. These would facilitate the sort of mixed farming he aspired to by greatly easing cattle and sheep droving to southern markets and also benefit the west coast fishery, not by assisting the transport of the product to market as with farming (the fish would continue to be shipped south by sea) but by allowing more rapid communication of intelligence about where shoals of herring were appearing the fishers could respond to.

Fishing boats in Loch Hourn in 1815 by William Daniell

Telford's report was endorsed by a select committee of Parliament and the result was two Acts of Parliament passed in 1803, one of them to build the canal and the other creating the Highland Roads and Bridges Commission. By 1820, this had overseen the building of 875 miles of road, nearly all of it still in use today, as well as ten major bridges at a total cost of about £450,000 (about £30 million in today's money). I'm going to come back and write about the Commission again in future posts but I'll conclude this introduction to the topic by noticing two canals Telford considered but which didn't get built.

The part of the west coast considered most ripe for development of its fishery was what Telford called "the lochs at the back of Skye", that is the coast north from Ardnamurchan and including sea lochs such as Loch Hourn pictured above. To ease the passage of fishing boats there from the east coast it was seriously asked whether it might be possible to make another canal from the Caledonian to the west coast through either Glen Garry to Loch Hourn or Glen Moriston and Glen Shiel to Loch Duich. Telford dutifully walked both glens, out via Garry ("a very rugged and precipitous track") and back via Shiel and Moriston ("along the vestiges of a military road"). His conclusion was that it would be possible to make roads through these glens but dismissed the idea of "water conveyance" through them as "altogether unadvisable". I expect that's because the watershed of the lower of these two passes, Glen Garry, is at 718 feet only 2.6 miles from the west coast at Kinlochourn. On analogy with the numbers of locks to the summit levels of the Caledonian and Crinan Canals (106 & 64 feet respectively), that would have meant something like 90 locks in that 2.6 miles! It's interesting, though, that the very geography which made these glens impractical for canals (high summits close to the sea) was what made them ideal for hydro-electric development a century and a half later (see here).

A bit less of a no hoper in the canal stakes was one (red on the map above) just five miles long from the sea at the head of Loch Eil to Loch Shiel (a fresh water loch) which the fishing boats could then sail down and enter the sea again at Loch Moidart via the River Shiel and thus avoid a longer route down Loch Linnhe, up the Sound of Mull and round the Point of Ardnamurchan.

Telford performed some measurements and found that Loch Shiel was only 7' 7" above sea level and the summit level between between it and Loch Eil was only 43' ASL. So far so good in canal building terms except there was no river or burn at the summit level to keep the canal full of water. It could only be supplied by Loch Shiel itself so the bed of the canal would therefore have to be on a single level 12' below Loch Shiel and 6' 5" below sea level to give vessels entering sufficient depth at low tide. But that would mean digging 47' 5" down from the summit over a distance of about a mile. Telford suspected rock would be encountered and concluded regretfully that it wasn't feasible. He didn't rule out revisiting the proposal once the Caledonian Canal had opened, though, and it was obviously a still a live enough proposal to be included on a map published seven years later in 1810 (below). But by the time the Caledonian Canal finally opened in 1822 - to lower specifications than planned but nevertheless over budget and behind schedule (Sound familiar? Another subject I may come back to!) - the enthusiasm for canals had cooled and the Loch Shiel Canal was never heard of again.

Kirkwood's map of Scotland, constructed and engraved from the best authorities, 1810

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