Gradient Help

[Andy873]

Did they buy up the canal? A number of railway companies did, for the alignment, and in some cases (such as the GWR buying the Bridgwater & Taunton canal) for the water supply. Once the railway came along canals lost most of their trade, so were a cheap purchase.

Not that I'm aware of.

Probably not a matter of the railway builders choosing to follow the canal, more that both canals and railways were built to take advantage of the natural features of the land to minimise gradients, structures and earthworks. So in a lot of ways they were asking the same question and getting the same answer.

Thanks, that's a better way of describing the route taken.

With regards to the actual route taken - I've been making a series of maps using the OS 1844-45 series from the National Library of Scotland. There is an 1870 OS map available online but not suitable for me to use, however there seems to be little change from the 1845 one.

Firstly the station at Gt. Harwood. The main buildings were placed right at the bottom left corner of a field. All the fields around (including this one) are divided by hedgerows. It also appears that Station Road from Hey's Lane to the station followed the left hand side (North) hedge.

Next, going west there are four new bridges all again following an existing hedgerow.

And my last one so far, carrying on west, the line came to a wood called Norden Plantation. Apart from a small cut through, the line follows the northern edge of the plantation. This section was a 0.6 mile cutting with a gradient of 1 in 90 rising westward.

The bottom line that I can see so far is the L&Y were using features to follow as a guide as well as the best route they could attain without too severe gradients.

 

[Gloster]

As a slight irrelevance, I was looking up something in my copy of the gradient profiles book and saw that there is a station called Bogart between Lairg and The Mound/Golspie. (This is not the first time I have discovered such new stations: the index of my 1978 edition of Baker’s Atlas includes, in the correct alphabetic place, a station called Findf*ck on the London Midland Region in north-west London.)

 

[Mcr Warrior]

As a slight irrelevance, I was looking up something in my copy of the gradient profiles book and saw that there is a station called Bogart between Lairg and The Mound/Golspie. (This is not the first time I have discovered such new stations: the index of my 1978 edition of Baker’s Atlas includes, in the correct alphabetic place, a station called Findf*ck on the London Midland Region in north-west London.)

Could be typos or might possibly be deliberate 'mitsakes' introduced as a copyright protection measure.

 

[Taunton]

I seem to remember that the earliest editions of the Baker atlas were from before publishers had computers to sort the index alphabetically, and his university computer department did it for him, entering each entry on a mainframe punched card and then printing the sorted list. Good chance of a typo getting in.

 

[snowball]

I seem to remember that the earliest editions of the Baker atlas were from before publishers had computers to sort the index alphabetically, and his university computer department did it for him, entering each entry on a mainframe punched card and then printing the sorted list. Good chance of a typo getting in.

In the preface he thanks his cousin, Dr Tony McCann, for computer sorting the index. I didn't know Baker but I did slightly know Tony McCann, who was a lecturer in computer science at Leeds University, where I also worked. In the early 1980s (fourth) edition which I have, the university is not mentioned, nor are punched cards.

 

[Xenophon PCDGS]

Just as a matter of historical interest, there was a reasonably short railway section from Middleton Junction railway station to Oldham Werneth railway station. Was that similar in length and gradient as the one suggested previously?

 

[jfollows]

https://en.wikipedia.org/wiki/Oldham_Branch_Railway says

Connecting the two stations the branch was 2 miles (3.2 km) long most of which was the Werneth Incline at 1 mile 1,383 yards (2.874 km) long it was one of the steepest passenger worked railway line in Britain, with a gradient of 1:27 for about one mile (1.6 km).[1]

 

[Taunton]

https://en.wikipedia.org/wiki/Oldham_Branch_Railway says

Just as a matter of historical interest, there was a reasonably short railway section from Middleton Junction railway station to Oldham Werneth railway station. Was that similar in length and gradient as the one suggested previously?

I never quite got the unique claims of the 1 in 27 on the Middleton line, as the Mersey line from Hamilton Square to James Street is stated at 1 in 27 on both sides of the tunnel under the Mersey. The longstanding 1938/56 electric units there also had only just about half the power of the comparable 1939 units on the totally flat Liverpool to Southport line, so it is not as if great power is needed to handle such gradients.

 

[Gloster]

I thought that one of the points about the Oldham incline was that sections were even steeper than the official figure due to subsidence.

 

[edwin_m]

I never quite got the unique claims of the 1 in 27 on the Middleton line, as the Mersey line from Hamilton Square to James Street is stated at 1 in 27 on both sides of the tunnel under the Mersey. The longstanding 1938/56 electric units there also had only just about half the power of the comparable 1939 units on the totally flat Liverpool to Southport line, so it is not as if great power is needed to handle such gradients.

Probably more a matter of adhesion (proportion of weight on motored axles) than power. I don't know he details of the Mersey units but that ratio is likely to be much higher than for any sort of freight train.