Up to the sixteenth century, wooden shovels and picks are known to have been employed, and shovels were merely iron-shod. There is in the British Museum a MS. calendar of Haroldstone in S. Wales, of the early sixteenth century, in which are representations of the works of the months, and in it the labourers in the fields are shown as using wooden spades shod with metal.
German mining was carried on upon better principles than the English, and Sir Francis Godolphin sent for an experienced German engineer to instruct the miners of Godolphin and Tregonning in the superior systems employed in Saxony. It was then only that the hydraulic stamps were introduced.
In 1742 one steam-engine only was found in the county; but speedily after came a great advance. Savery and Newcomen brought in their steam pump; that of Newcomen was introduced at Chasewater in 1777.
Notwithstanding that the methods of descent into the mines by a series of long ladders had been superseded by the man-engine, first introduced in 1842, it was a long time before the old ladders at different successive stages were abandoned.
Owing to the introduction of tin from the Straits Settlements, where it is found in the condition of stream tin and can be easily worked, the tin mining in Cornwall, necessitating real mining and the following of lodes, has proved unremunerative and has been abandoned, and now but few mines are worked for the metal. Another cause has fatally affected Cornish mining—the fraudulent practice of the promoters of the mines. It was no uncommon practice for the "captains," when a rich lode was struck, to cover it up, and follow false lodes, till the investors in the venture lost heart and refused to advance more money, when the captains would carry on the work in the real lode, if they could raise the capital, but this they often failed to do, the mine having fallen into discredit, or the water having broken in.
But if tin mining be practically dead in Cornwall, another industry has risen with leaps and bounds. It is that of the china-clay and china-stone, employed in the manufacture of porcelain, in the sizing of paper and of cotton materials, in the manufacture of alum, etc. The glazed paper so largely employed in our illustrated papers is made up largely with china-clay. Some years ago the Italian government employed this paper for its official documents, but found that after a few years under the influence of damp weather the records had dissolved into a lump of clay.
China Clay Quarries
China-clay consists of decomposed felspar, quartz and white mica. In 1817 the amount shipped for manufacturing pottery was comparatively small, but of late years it has grown, and employs over 3000 persons. The china-clay is the same as the Chinese Kaolin; its value was discovered by a Plymouth Quaker, Mr Cookworthy, in 1745.