The Wheels Wreck Report


Report on photographs and drawings offered by Todd Stevens
 of the ‘Wheels Wreck’ to the Trevithick Society, October 2010

1.           During 2010 the Trevithick Society received a number of underwater photographs and detailed line drawings.  These were sent by Mr. Todd Stevens, a diver of some 30 years experience who lives on the Isles of Scilly and is known for his discovery of HMS Colossus in 1999 and ten other subsequent wrecks.  The pictures were purported to be related to a wreck of a ship and its cargo he had found lying in 18-20 meters of water off the island of Little Ganninick in the Isles of Scilly.

 2.           The significant parts of the cargo consisted of cast iron objects apparently designed for mechanical use.  Mr. Stevens referred these photographs to the Trevithick Society, established 1935, because of its authoritative interest in industrial archaeology especially that of foundries and mining related to the prolific mining and engineering period from 1750 to 1900, a period in which the ship had apparently foundered.

 3.           No member of the Trevithick Society has any experience of underwater exploration and the following remarks are based entirely upon examination of the illustrations presented by Mr Stevens.

 4.           Whilst examining the illustrations, the Society has taken care not to jump to any conclusions, nor to speculate beyond offering explanations for what appears to be shown in the illustrations.

 5.           A factor that precluded close examination of the artefacts was the amount of natural concretion that had accumulated over the years.  If there has been research into the speed at which such concretion builds in this sea area it may assist in the establishment of the date of the foundering but that is outside the knowledge of this Society and the functions of this report.

Before offering a detailed consideration of each item there are a few general observations.

 6.           The photographs revealed a jumble of what appeared to be cast iron objects lying where they had fallen upon impact with the sea bed and possible movement caused by subsequent deterioration of the wooden-hulled vessel that was transporting them.  There was no apparent sign of a violent impact and there is little sign of damage.  Many of the artefacts remained piled upon each other, a factor that precluded a close examination of the items hidden below the uppermost ones.

 7.           As far as can be seen from the illustrations, it is difficult to piece together more than a few of the items in order to creat a total mechanical device.  This means that we do not think we are looking at one dissembled pumping engine or locomotive, rather an assortment of castings that may have some relationship to each other.

 8.           The cargo could have been a delivery to one or more customers for use, including possible use as replacements, in a water pumping engine and for the construction of tram track wagons.  This widens the possible destination, the purpose of the cargo and little more can be ascertained unless there is access to the remainder of the shipment and some, at least, of the concretion removed.

 9.           This suggestion raised the distant possibility that, if the cargo was destined for a newly established mining or other engineering requirement, the remainder of the equipment may have been shipped in another vessel.

 10.        However, taking a purely economic view, it is unlikely that the whole assembly of equipment usually found at a mine or other industrial site would have been ordered and delivered at the same time.  Careful probing of the ground or development of a business would reveal the need for certain items of equipment and these would have been ordered as they were required, probably over a period of several years.

 11.        While some items apparently reveal their ultimate destination to be associated with the pumping of water possibly for human consumption, the existence of so many tram wheels is not a significant part of a water pumping exercise unless they were intended for wagons required to transport fuel (coal?) to fire the pump’s boiler.  It would, presumably, be the intention to construct the wooden wagons near the destination.

 12.        There is the possibility that the variety of artefacts could have been ordered by an agent of the foundry and were destined for more than one customer.

 13.        Members of the Society have had difficulty in identifying some of the items.  Although many are clearly connected to a steam operated water pump, many are not directly related to any commonly known steam engine and have possibly been made for a bespoke machine or machines designed for some process that are not evident from the evidence in the pictures.

 14.        It is important to state that the cargo did not apparently contain a steam boiler shell or the usual beam or bob that one would expect if the ship had been carrying a complete steam pump.  There is the possibility that, had they been aboard, these items would have been stowed below the other, more insubstantial, items to avoid damage to the latter during the voyage.  The beam of a pumping engine commonly weighs 10 – 20 tons.  Of course, these items may be found below the ones in the photographs, this remains to be seen.  A beam would, almost certainly, bear the maker’s name.

16.        There appear to be some significant boiler fire tubes in the cargo.  These are the types of tubes we would recognise today as boiler fire tubes.  History books refer to multiple fire tubes from about 1810 but these were very experimental, usually failures and unrecognisable compared to those on the wreck.  These earlier tubes were made in a variety of shapes from wrought and cast iron, sometimes copper.  The simple, single fire tube as found in the ubiquitous ‘Cornish’ boiler (except, of course, the double ‘Cornish’ boiler) held sway for many years.  Brunel specified ‘Cornish’ boilers for the original engines of ss Great Britain that was launched in 1843.

 17.        It was not until the early 1830s that we see any signs of successful manufacture of multi-tubed boilers. Stephenson’s Rocket locomotive used such tubes at the Rain Hill Trials in 1829. It would be a few years later before we see a recognisable fire tube in series production. If these tubes are, as they appear, to be replacements we have to consider that the boiler for which they are required has been in use for sometime in order to require replacement tubes; this suggestion adds a few years.

 18.        There is considerable food for thought that might eventually reveal the purpose of the parts not directly associated with the water pump and the date of their intended delivery. These parts were expensive and clearly intended to be put to some profitable use.  In the early Nineteenth Century there were few heavy engineering processes as we know them today.  Food was prepared in villages, bricks were made wherever clay was found with fuel and virtually every creek in the land had its own boatyard.  Many cotton mills became fully mechanised by the mid-19th Century but they did not require complicated water equipment and deliveries from foundries to mills would not have been routed around the Western Approaches.  The provision of water for human consumption in major towns and cities became paramount at this time and the first significant pump for Kew was built in Hayle in 1846. This was followed by a larger pump built in 1869.  Similar pumps had already been built in quantity for mines throughout this country and abroad.  Pumping systems like Kew were unlikely to require some of items found in the cargo.  In his report of 6.12.2009 Mr Stevens suggests a possible date of the disaster in the region of 1850.  From the evidence we have seen, we would not strongly disagree with this and may add a few years.

 19.        The search for a process that could have used the relatively complicated industrial hydraulic items in the cargo must narrow the field for the ship’s destination.  This is where the Trevithick Society must defer to general industrial archaeologists but will offer some thoughts that could indicate how further research might be undertaken.

 20.        Iron products, such as those in this cargo, would usually have been produced in a foundry that had easy access to both coal and iron.  As there are apparently a number of rising main water pipes the shipment could have been intended for a mine.  We have to suppose that mine, even if it was a coal mine, was not close to a source of iron or it would have had a nearby foundry to supply all its cast iron requirements.  So we are therefore looking for a coal mine that requires sophisticated hydraulic machinery and does not have substantial iron deposits nearby.

21.        The selection of coal from stone at the pit head was originally undertaken by hand, mechanical selection was commenced at some mines in the 1840s and hydraulic selection or ‘washing’ was introduced about twenty years later.  A History of British Coal Preparation. John Hillman, 2003.   A number of mines in Kent produced coal, very little iron and suffered severe problems and many deaths from water ingress. The Dover mine, that could have needed to buy in washing equipment, did not commence serious production until 1886, rather later than the date that has been attributed to the foundering.

 22.        The many apparent tram wagon wheels in the cargo are difficult to date although they were probably prior to the Dover mine. Such wheels were used over a considerable period of time and, from the 1820s, the trams were often pulled by steam locomotives.  The wheels do not appear to have flanges. this indicates that the rails, of which we have so far seen none in the cargo, would have been made with flanges.  In a cargo of such variety with what appear to be replacement parts, we would expect to see replacement rails as these were frequently broken in use.  The use by the recipient of flanged rails could be an indicator of the destination and, possibly, indicate the date of the foundering.

23.        The Society will not comment on the position of the wreck other than to say that, whatever course it might have been steering to a UK destination from any foundry on the mainland, it was grossly off course, a possible cause of the disaster.  Other factors supplied by Mr. Stevens concerning the possible condition of the ship when it sank and a study of weather reports may help in ascertaining the date of the foundering. The ship may, however, have been intending to sail to a foreign port.  If that is to be considered it would have to be one where there was access to large quantities of fuel and water.  That would exclude, for instance, the West Indies.


Figures 1 & 2


 As suggested on the drawing, these two drawings depict two components of the same wheel.  They would have been joined together with wooden spokes that might have been in place at the time of the sinking.  The relatively fragile nature of a ten foot cast rim is likely to have necessitated its sensible location on top of more robust components.


The complete wheel was clearly intended to transmit power in some way and this is indicated by the large sectioned hole in the centre.  Its purpose is unknown at this stage; we cannot clearly link it to a water pump.



Figure 3. 

As this large component appears to rotate in some way it is likely to have formed part of a powerful machine that would have incorporated a substantial base that does not appear to be a part of the visible cargo.

Figure 4.

 Again, this could be part of a machine, or machines as there are apparently three of the components on site; possibly part of a machine made by an individual manufacturer for use by single operator.


Figure 5.

Typical access cover for a water clack valve.

Figure 6.

While this is described as a solid iron component subsequent examination has revealed that it is hollow and could have a number of holes that are completely hidden by concretion.  If this is the case, it could be a sieve located at the foot of a rising main pipe.

Figure 7.

This is another very substantial piece of equipment that was clearly built to transmit considerable power in some way.  It is difficult to associate it with any part of the water pump items in the cargo and its purpose is currently unknown.

Figure 8.

One of the few items to have been damaged.  Bespoke manufacture for a specific purpose that would have involved a considerable flow of water.

Figure 9.

A specially made object (rod) that probably has holes in it that have been filled with cementation. Otherwise it could be difficult to locate or use.

Figure 10. 

As can be seen in the photographs, there are a great number of these straight pipes in assorted sizes and there appear to a quantity of bends in the photograph that shows the rim of the 10’ gear wheel. They could have been intended for a complicated processing plant that is not directly connected to the water pump other than the latter provides the water for whatever the process is.  Such complex plant indicates a fairly late date.

Figure 11.

 There are apparently a great number of these pipes on the wreck site and many are swaged at one end.  These are very likely to be replacement boiler fire tubes.  The other end of the tube would be swaged when the tube was inserted into the boiler.  The fact that there is apparently no boiler shell indicates that the shell is already on site at the destination (or under the other items or on another ship) and that these are replacement fire tubes.  Had the tubes been intended for a new boiler, that boiler is likely to have been shipped complete with the tubes in situ; such shipments of heavy items had been undertaken for many years.  Also, the possibility that a multi-tube boiler existed long enough to require replacement tubes indicates the wreck probably occurred later than has previously been considered.  The variety of swages could indicate that the fire tubes are intended for more than one boiler at the destination, or destinations.

Figure 12.

This cable carrying, sheave wheel is not similar to that found in many industrial and mining scenes.  The purpose of such a wheel is to transfer energy and at that time would usually require a substantial axle on which the wheel would turn, this wheel would not appear to accommodate such an axle.  Also, the recess for the cable appears to be insufficient for normal use unless the design incorporated a tight cover.  There is no sign of this and designs at the time did not usually include this feature.  


A word about boilers.  It was not unusual for new boilers to be shipped complete with all fire tubes installed.  We have seen no evidence of such a boiler or a boiler shell.  There has been the suggestion that a broken cylindrical item in the cargo may have been a boiler shell.  Whatever it was, a boiler shell would probably be the largest and heaviest item in the cargo.  Along with the beam, it would have to be substantial in construction and probably placed at the bottom of the hold to avoid damage to lighter items.  These are also likely be the last items to break in a shipwreck.


We have seen evidence of a wooden ship carrying a mixed cargo of cast iron items.  While it has been possible to identify several items in the cargo, we have not been able to find a relationship between many of them.

At the time of the foundering, the prime form of industrial and transport power was the high-pressure steam engine and this could have been used for a variety of industrial purposes.  We have made some suggestions in the foregoing pages of possible uses for the items found in the wreck but it is stressed that this is conjecture.  There are so many items built to a great variety of designs, some in quantity, and we are left with an intriguing mystery as to their purpose.  These are not insignificant items.

Until it is possible to lift some chosen objects for examination the true purpose of their manufacture and the whereabouts of the foundry in which they were made is unlikely ever to be known with certainty.  Once that information is to hand it could be possible to identify the destination and purpose for which so many expensive, carefully made iron castings were required.  One has to consider that some historical group may know the purpose of these items but is unaware of their existence or is intrigued why the company they are studying suddenly failed in the late Nineteenth Century.  We recommend further study.

While the Trevithick Society owns the content of this report it takes no responsibility for the information or suggestions it contains.  Its contents may suggest possible explanations and are offered to enable further investigation to be undertaken.  The loss of such a significant cargo during the Industrial Revolution was an enigma that must have had considerable consequences for both the foundry and the recipient, wherever they were.  The cargo would have been difficult to replace quickly and its loss would surely have had consequences for the community of workers at the journey’s end.  At this stage we do not know the name of the ship or the fate of its crew but wish Good Fortune to those who will continue the investigation.

© The Trevithick Society

October 2010.