[2][page needed][5][note 1] Tyrwhitt ceremonially laid the first rail on 12 August 1819, but in fact contracts had not yet been let for the construction, and some re-appraisal of the engineering of the railway was to intervene.

However, the wharf would only be accessible at high tide and the river approach was lengthy and awkward, and it was decided to extend the course of the railway westward to reach Sutton Pool.

A contract for the construction of the formation was let to Hugh McIntosh of London in June 1820, for 9s 3d per yard; it was to be a single line with a number of passing sidings (referred to as "turnouts")—two per mile.

They had acquired tenancy rights to extract granite from Dartmoor and needed to bring it down to Plymouth for use there in the breakwater project, and to coastal shipping for onward transit.

[2][page needed] On 26 December 1820 the engineer Stuart reported that Shillabear's route as far as Jump (later called Roborough) which ran via Fursdon was too steep for horse traction.

The new route needed to pass through the lands of the Earl of Morley, and he had a slatestone quarry at Cann; this was not far from the proposed line, but at a lower level in steeply sloping terrain, and the other side of the River Plym.

Hopkins was now in charge as sole Engineer, he modified the specification for the later batch of rails; they were to be 3 ft 10 in (1,170 mm) long, with lapped joints at the sleeper blocks.

[8][page needed] The finances of the company during the construction phase had been extremely difficult, and work had only been kept going by repeated Exchequer Loans and other financial arrangements.

The extensions to Sutton Pool and to Princetown were therefore carried out by the Johnson Brothers as contractors, and in return they took a mortgage on the company and were able to offset their tolls against the sums due.

However, Kendall reports an extract from a "chronicle in diary form compiled by one William Bray, sometime Rector of Tavistock"; approaching King's Tor he found that Some huts, one a blacksmith's shop now presented themselves, and before this stood a vehicle not much unlike a rude kind of vis-a-vis with an awning.

The dominance of Johnson Brothers traffic is shown by the return of receipts from 26 September 1823 to 5 July 1825: Now however the Earl of Morley demanded that the commitment of 1821, to connect his Cann Wood Quarry to the line, should be honoured at once.

[17][page needed] The seven-year agreement with the Johnson Brothers had given them an effective monopoly of granite transport until 1834, but on expiry of that period no other trader came forward to challenge their established position.

The line was effectively the private property of the Johnson Brothers and it appears likely that they made some payments on account to prevent premature seizure by the Exchequer.

[19] Johnson Brothers' activity increased with the years; Rachel Evans, writing in 1846 passed the quarries: An immense excavation presents itself studded with workmen ... some are boring holes in the flinty rock; others are filling the cavities with powder; some are chipping the rude blocks into shape; others are lifting their ponderous weight by cranes and levers; horses, carts and railway waggons, are in constant employment, to convey away the heavy masses of stone, (some twenty feet in length) which have been available in the principal public works, lately carried on in the metropolis: the Post Office and London Bridge, were constructed of this strong material, and at present it is furnished for building the new houses of parliament ... Three hundred men were recently in constant employment on the spot.

[20][page needed]The P&DR railway was a horse-worked line with short cast iron rails on stone blocks, using a track gauge of 4 ft 6 in (1,372 mm), built with the intention of improving the moorland areas around Princetown.

The main line descended from Princetown to Crabtree, east of Laira, following a very sinuous course in an attempt to limit the maximum gradient for the uphill haul; extremely small-radius curves were adopted in places to avoid major earthworks.

The wagon structure was founded on two main beams 9 feet (2.7 m) long, with the bed formed of 2+1⁄2 inches (64 mm) planking armoured with longitudinal iron strips.

The section from Plympton to the junction near Marsh Mills was sold to the SDR and closed in 1847 to allow them to construct their main line without the necessity of making a crossing of the P&DR.

[8][page needed] Lord Morley seems to have acquiesced in this; his china clay traffic from Lee Moor used Plympton as a railhead and he may have considered the SDR a more efficient carrier from there to Plymouth.

The SDR obtained powers in the 1846 session to take over the P&DR line between Crabtree and Sutton Pool, but the terms were subject to negotiation, and this proved difficult and slow.

The triangular junction between the line to Sutton Pool and that to Cattewater had very short radius curves, but this area (referred to as "the Granite Works"), and wharves at Laira, were horse-operated for the first years.

Work started on building the Lee Moor branch in September 1852: it was to be an intrinsic part of the SD&TR lines, and possibly on the broad gauge.

[2][page needed] The heavy mineral commodity being extracted by William Phillips, lessee of Lord Morley was situated on Lee Moor at an altitude of 900 feet (270 m).

Some minor alignment improvements were made to accommodate locomotive working, and a major section of new route to pass east of Yennadon Down and to descend to the Tavistock line at Yelverton.

The dominant traffic was china clay downhill to the Cattewater or Laira exchange sidings and stores and coal uphill to Lee Moor.

From 1936 the section above Torycombe incline ceased to be used, and the operating company increasingly installed pipelines to transmit the china clay in slurry form, and also by road.

The owning company did not wish to relinquish the right of way, however, and token movements carrying sand from Marsh Mills to Maddock's concrete works were made at three-monthly intervals.

This continued until the final movement on 26 August 1960, the last time the Lee Moor Tramway horses pulled wagons across the Great Western Railway main line.

[8][page needed] In 1844 two Plymouth businessmen, Jacob Hall-Drew and Peter Adams, attempted to generate a business in processing peat to make naphtha.

Given the shortage of money it seems likely that the temporary northern terminus was on the approach to Kings Tor; there are indications on the earliest available Ordnance Survey map (1884) that support this.