Assistance Please: 18th century granite trackways for early mines. Rocket questions.

[Chops]

Whilst in Devonshire (memory fogs, maybe Dartmoor) in '67, I vividly recall these granite trackways laid into the earth dating to perhaps the 1700's, upon which carts were hauled by pit ponies, typically coal (?), I recall. Try as I might, I cannot conjure the correct wording to locate an image of this artifact on the internet. I am to give a presentation to the local Rail Historical Society next week, and greatly need this image in the discussion of first generation steam locomotion and its antecedents. Would someone kindly post me an image or URL?

 

Two other questions vex me: I cannot locate any information in either prints of the age nor in writing as to how water from the barrel on the tender was delivered to the Rocket's boiler. Sounds simple, but in 1827 one could not simply buy a hose off the shelf. I am guessing they had to make it from scratch. Leather with rivets was one option in the early 19th century, but no evidence seems to exist as to how this connection was made. Any resources or ideas? 

 

Thirdly, somewhere I came across information that the Rocket's operating boiler pressure was 60 PSI. Where did the pressure gauge come from??? Again, not something that could be grabbed off the shelf, and "high pressure" steam was in its infancy. 

 

Thank you in advance. 

 

 

Edited October 4, 2023 by Chops

[Dunalastair]

Are you thinking of the Hay Tor tramway?

 

https://en.wikipedia.org/wiki/Haytor_Granite_Tramway

 

Dates from 1820.

[LMS2968]

Rocket's boiler pressure was 50 p.s.i., the limit allowed by the Liverpool & Manchester Railway under its rules for the Rainhill Trials. The gauge was a mercurial gauge mounted vertically alongside the the chimney and with its lower end connected to the boiler; the higher the pressure, the higher the mercury stood in the glass tube which was visible to the enginemen. See II and V! below.

 

 

[DavidB-AU]

1 hour ago, Chops said:

Two other questions vex me: I cannot locate any information in either prints of the age nor in writing as to how water from the barrel on the tender was delivered to the Rocket's boiler. Sounds simple, but in 1827 one could not simply buy a hose off the shelf. I am guessing they had to make it from scratch. Leather with rivets was one option in the early 19th century, but no evidence seems to exist as to how this connection was made. Any resources or ideas? 

 

Surprisingly you could buy leather hoses off the shelf in the 1820s! The Coste and Perdonnet drawings of Lancashire WItch show a hose (C) between the tender and the bottom of the feedwater pump (P). Rocket had basically the same system.

 

 

 

 

 

[Jeremy Cumberland]

Quick calculation: 50 psi is 8½ feet of mercury.

 

It's an interesting thought that early steam locomotive pressures could have been limited by the ability to provide a legible pressure gauge.

 

I also note from VI that the gauge only needs to be readable above 45 psi. This is very practical in terms of construction, for only the top of the tube will be in glass, but it must make managing the engine a little tricky.

 

Edit: It might have been a float operating a pointer, I suppose, rather than a glass. 45 psi to 50 psi represents a 5" change in the height of the column.

Edited October 4, 2023 by Jeremy Cumberland

[Chops]

Thank you most kindly! At least now I have some insight, herein. Wish me luck on my presentation, which will include those two gems. Small details, but details on which the entire Stephensonian project would not be able to go forward without. 

 

And yes, the Hay Tor tramway, or something a lot like it. I saw that, or something just about identical, at the age of six or seven. Even then it struck me as something really remarkable. That it precedes railways to come is something well worth noting. 

 

 

[009 micro modeller]

25 minutes ago, Chops said:

And yes, the Hay Tor tramway, or something a lot like it. I saw that, or something just about identical, at the age of six or seven. Even then it struck me as something really remarkable. That it precedes railways to come is something well worth noting. 

 

 

I have a magazine somewhere with an article about Hay Tor, which also refers to a couple of other similar lines if that would be useful. IIRC I think one of the notable features of the Hay Tor line was its relatively late build date compared to other lines built in a similar way, so there is more left to see. There are holes in the stone at points which apparently originally had small moving wooden parts to direct the wagons.

[Rivercider]

1 hour ago, 009 micro modeller said:

I have a magazine somewhere with an article about Hay Tor, which also refers to a couple of other similar lines if that would be useful. IIRC I think one of the notable features of the Hay Tor line was its relatively late build date compared to other lines built in a similar way, so there is more left to see. There are holes in the stone at points which apparently originally had small moving wooden parts to direct the wagons.

We visited Haytor a few years ago and spent quite some time exploring to visible remains of the Granite Tramway.

Understandably some of the granite blocks are in better condition than others, there is also what seems to be a 'prize length' where the track has been better cleared of soil and scrub.

 

 This was on the Holwell Tor Quarry branch of the tramway, I think that might be one of the holes associated with the operation of the pointwork. There is some debate as to whether theplate at the points was made with metal or wood, I don't think any have been found. 19/5/2021

 

 

This is the junction, the Holwell Tor Quarry branch leads away down to the right. 19/5/2021

 

cheers 

[Chops]

On 04/10/2023 at 01:03, Jeremy Cumberland said:

Quick calculation: 50 psi is 8½ feet of mercury.

 

It's an interesting thought that early steam locomotive pressures could have been limited by the ability to provide a legible pressure gauge.

 

I also note from VI that the gauge only needs to be readable above 45 psi. This is very practical in terms of construction, for only the top of the tube will be in glass, but it must make managing the engine a little tricky.

 

Edit: It might have been a float operating a pointer, I suppose, rather than a glass. 45 psi to 50 psi represents a 5" change in the height of the column.

From what images I deduce perhaps a metal sleeve with some kind of projection out the top, that might appear to be a "float," if indeed I am looking at the correct item.  It appears to be in the vicinity of the right piston. 

 

What troubles me now is if the mercury gauge is connected directly to the steam boiler, as a manometer in schematic appears to be, how does one calibrate for the expansion of the mercury caused by the heat of steam, which might be greater than 600 degrees Fahrenheit? Is the volume of mercury somehow calibrated to account for the expansion of the heat???

 

 

Another question: bearings. In a horse drawn carriage, with a speed range not very fast, friction of wheel upon axle is perhaps considerably less than a railway carriage at 27 MPH. Apparently, bearings microscopically squash from the load, and the race, in which they travel is designed to redistribute some of that pressure to reduce this deformation. The tolerances are incredibly tight, and the effect of this deformation is incredibly real, and the faster an axle turns, the more amplified is the vibration and friction. 

 

What manner of bearings did the Rocket and its carriages ride upon???

 

One of Robert's letters to George, worries about the expansion of the rear boiler plate bulging outward to a depth of 1/8th of an inch! This subsumes that A. this was recognized as a fail point, and B. they had the ability to measure things down to an astonishing degree! (Stephenson, Sr.'s response was to insert a series of stays that connected front and rear boiler faces in a longitudinal manner, the length of the boiler, e.g.). 

 

Again, thank you for your thoughtful replies, my understanding of the scintillas of this brilliant prototype is enhanced. 

 

[Chops]

[Jeremy Cumberland]

2 hours ago, Chops said:

What troubles me now is if the mercury gauge is connected directly to the steam boiler, as a manometer in schematic appears to be, how does one calibrate for the expansion of the mercury caused by the heat of steam, which might be greater than 600 degrees Fahrenheit? Is the volume of mercury somehow calibrated to account for the expansion of the heat???

Interesting. The coefficient of expansion is 0.00018 per degree Celsius. 50 psi is 101.8 inches of mercury. At 200 degrees C above the calibration temperature, the expansion would be 3.7 inches, which represents 3.6 psi in a manometer. This probably isn't worth bothering with, but I expect they tried to shield the gauge from the heat of the chimney. I doubt there was much heat transfer from the steam -- it was probably water by the time it met the mercury, and in any casre the steam temperature was only 138 degrees C.

 

3 hours ago, Chops said:

Another question: bearings. In a horse drawn carriage, with a speed range not very fast, friction of wheel upon axle is perhaps considerably less than a railway carriage at 27 MPH. Apparently, bearings microscopically squash from the load, and the race, in which they travel is designed to redistribute some of that pressure to reduce this deformation. The tolerances are incredibly tight, and the effect of this deformation is incredibly real, and the faster an axle turns, the more amplified is the vibration and friction. 

 

What manner of bearings did the Rocket and its carriages ride upon???

You talk about roller bearings, but I don't think roller bearings were widely used in engines until the twentieth century. These bearings were almost certainly plain brass/whitemetal, which had been used in engines since the early eighteenth century, and probably date back before this. I doubt the locomotive's moving parts had much in common with contempary road carriage construction.

 

3 hours ago, Chops said:

One of Robert's letters to George, worries about the expansion of the rear boiler plate bulging outward to a depth of 1/8th of an inch! This subsumes that A. this was recognized as a fail point, and B. they had the ability to measure things down to an astonishing degree! (Stephenson, Sr.'s response was to insert a series of stays that connected front and rear boiler faces in a longitudinal manner, the length of the boiler, e.g.). 

Measuring distances is easy if you have a reference point, and 1/8" is hardly "an astonishing degree". Vernier calipers were invented in the seventeenth century, and must have been common in the 1820s.

[LMS2968]

Could I suggest 'The Engineering and History of Rocket' by Michael R Bailey and John B Clithero (2000), National Railway Museum, ISBN 1 900747 18 9. All the answers are in there, including a photo of a bronze axlebox with oil boxes cast in and oil holes into the box and lubrication grooves in the bearing surface.

 

By the way, that drawing is totally wrong about the firebox shape so don't trust it for anything else either.

Edited October 9, 2023 by LMS2968

[Chops]

More and more is revealed. Thank you!

[Chops]

My presentation went well, and I have been invited again to present on (American) Civil War Railroads. Thank you all for your most illuminating replies. My interest in history is typically upon mankind's interaction with technology. 

 

The Common Wisdom as to what defines the activities of us, Sapiens, is the control of fire, ceremonial burial, purpose built tools and art. In turns both fascinating and frustrating, the dial keeps getting pushed back on those indices. Preceding Sapiens by about 2.25 million years, a half chimp, half human collection of skeletons in the Rising Star Cave of South Africa has demonstrated all four. 

 

This leads me to the postulation that the activity that defines mankind is the lever and weaving. No other species of ape does those things, or has done those things, Cro Magnon and Neanderthal thought to use animal skins, albeit sewn. But neither weaving or levers, the latter being introduced in the form of the atlatl, or, if  you will, a . I define a lever as a force multiplier. 

 

In this sense, Stephenson, et al, use of the piston is a new advance in the use of the lever. A giant leap forward for mankind. 

Edited October 19, 2023 by Chops

[Jeremy Cumberland]

12 minutes ago, Chops said:

In this sense, Stephenson, et al, use of the piston is a new advance in the use of the lever. A giant leap forward for mankind. 

I find the history of early steam power fascinating. The piston had been around for centuries, reputedly being invented by Ktesibios (285–222 BCE) in Alexandria, and several examples survive from Roman times. However these were pumps, with a force being applied to the piston rod to pressurise and move fluids, unlike in an engine where a pressurised fluid creates a force in the piston rod.

 

The first known working steam engine was built around 1698 by Thomas Savery. Steam was admitted into a cylinder or sphere, where it was condensed by a small amount of water to create a vacuum, which drew a mass of water from a depth into the chamber. The machine had several limitations, not least the depth from which water could be sucked, which was limited by the strength of the vacuum (an absolute limit of 10 metres, and in practice doubtless a lot less).

 

It took 14 years before Thomas Newcomen came along and worked out that by using a piston in a cylinder for the condending steam and another piston in a cylinder to pump the water, with the two piston rods linked by a beam, that water could be pumped from any depth. It was also very quickly found that that having moving pistons, rods and beams allowed the automation of the valves (as far as I am aware, the valves of a Savery engine needed to be worked manually).

 

Invention is a funny thing. Many inventions seem obvious, but that is only because we already know of their existence. Often they were far from obvious at the time. I particularly like James Watt's dismissal of James Pickard's 1780 patent of the rotative engine - surely one of the greatest inventions ever made - by saying that it was nothing more than an application of the crank, and cranks had been used since ancient times. However, it is an application that eluded Watt, for when in 1777 he wanted a steam engine to drive lineshafting to power the machines in his Soho works, he built a steam pumping engine to pump up water from underground, then used the water to drive a waterwheel. Pickard offered to go into partnership with Watt, but Watt was furious and refused. Now that he could see what he was aiming for, he quickly invented and patented the sun and planet gear, and just for good measure came up with four other ways of convering linear motion from a piston into rotative motion, and patented these as well, just to stop anyone else from sidestepping his patents like they had for the condenser.

 

Sorry, I've gone rather off-topic here.