Very much a piece of string. Knowing how many trips, with what load, would be part of the contractor's informed guesswork when tendering. Get it right, you're in profit. Wrong, and you join the thousands who went bust.
It does vary significantly with the type of "soil", but I'd have gone a bit heavier than that. Loosely dumped into a wagon, I'd allow between 1.2 t/m3 and 1.8t/m3 depending on the material and whether it self-compacts or not. That's about 0.9 to 1.4 t/yd3.
As dug from natural ground, or compacted in an embankment, density is between about 1.7 and 2.0t/m3, so Andy would need to allow for a bulking factor between bank volume (as dug) and volume in the wagon.
It did cross my mind that it was like how long is a piece of string?
Regarding what was moved from three cuttings:
Cutting 1, the first to be dug was described as "running sand" and "Quicksand" - 180,000 cubic yards.
No. 2, (next to cutting 1) was blue boulder clay, rock hard when dry, super slippery when wet. 200,000 cubic yards.
No. 3, (almost 0.5 miles away) was a mixture of blue boulder clay, flag rock, and shale. 300,000 cubic yards. All cuttings are made on an upward gradient.
The long embankment needed was in the other direction in a downward gradient.
Using the prices tendered on a nearby L&Y line construction (not this one) as a model, a figure of just over 1 shilling per cubic yard was quoted to dig, transport and tip earth / materials. 4s 6d was a labourers cost per day, so under this model a labourer has only to shovel 4.5 cubic yards in a day, anything more and you, the contractor are making money on top of the charge for moving all of it.
According to John Marshall, digging began 5th of April 1870, and the newspaper article from the middle of August (same year) has the following snippets:
A lot of men are involved in the construction - Frustratingly it doesn't say how many.
About two miles of the railway have been formed - It doesn't state the formation work along that length is actually completed to specification, just that it stretches roughly about two miles.
An engine can now be seen running backwards and forwards making ten trips a day, hauling 10 waggons each time - It doesn't state the capacity of the waggons, only that they are earth waggons, nor does it state the length of the track being used.
The engine takes the waggons from Harwood (station area and first cutting) to Harwood Valley where it is tipped - The geography around Gt. Harwood is that where the station is to be, to your left you have hills, to your right, the land slopes down to the river Calder.
I would be wary of trying to ascribe a ‘one size suits all’ approach to a particular local scheme.
Totally agree with that.
This section of the line (6.75 miles) was contracted to Mr. Stone, the easter shorter section (2.25 miles) was done by Mr. Gregson who went bust doing it. Because he went bust in 1874, I decided to look at what items he was selling by auction at his base in Padiham:
Firstly, 8 horses and various equipment associated with the build. What's interesting is that also on the list are twenty three, 2 yard earth waggons.
Do you think they mean 2 cubic yard waggons? @DelW's calculations suggest he's not far wrong?
Obviously different contractors might employ different tactics regarding a build but common sense dictates there must be some similarities. Perhaps Gregson's approach was to use horses to move the wagons, whilst Stone's approach might have been a combination of engine and horses.
Going back to Mr. Stone's section, the one in question with the engine - It could very well be it was his own temporary track that was used, however, the obstacle regarding gauge was the L&Y's insistence that as soon as a suitable length of formation work was complete (300 yards, and 300 feet away from any works), their track be laid. Now regardless of the engine, you can't run narrow gauge wagons on L&Y standard gauge track, surely? and that track is in your way.
One point to note - The newspaper article is written only four and a half months after work began, and with about two miles of formation work noted, Mr. Stone seemed to be getting on with things as fast as possible, taking advantage of the (hopefully) better weather from Spring to Autumn. The point of getting more done Spring to Autumn is something many of you have previously told me about and indeed does look to be the case.
And
@ThirteenArches points out, get you calculations wrong and you are in danger of going bust, as happened to Mr. Gregson, the other contractor.
What I do find confusing is the newspaper article mentioned is the only article I can find regarding any of the on going works during the line's construction? only after the line opened do we see articles about it. I'll keep looking.
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