"About 1804 Captain Trevithick put up in Dolcoath Mine a stone-crushing mill, having large cast-iron rollers, for breaking into small pieces the large stones of ore; it was spoken of as the first ever used for such a purpose; the same form of crusher is still used in the mines. It caused a great saving compared with breaking by a hand hammer."[1]

"I saw at the Weith Mine in 1805 a portable high-pressure engine, made by Captain Trevithick.

"It was called a puffer; the cylinder was in the boiler; the steam about 30 lbs. on the inch above the atmosphere. A wooden shed sheltered the engine and man.

"The facility of manufacture and cheapness of those engines caused them to be much used in the mines, and also elsewhere."[2]

"Mr. Giddy,

"Coalbrookdale, September 23rd, 1804.

"Sir,—Yours of the 13th this day came to hand. I left Wales about eight weeks since, and put an engine to work in Worcester, of 10-horse power, for driving a pair of grist-stones, and a leather-dressing machine, and another in Staffordshire for winding coals; each of them works exceedingly well.

"From Coalbrookdale I went to Liverpool, where a founder had made two of them, which also worked exceedingly well; one other was nearly finished, and three others begun. Some Spanish merchants there saw one of them at work, and said that as soon as they returned to Spain they would send an order for twelve engines, of 12-horse power, for South America. In South America and the Spanish West Indies water is very scarce; in several places there is scarcely water for the inhabitants to drink, therefore there is no water for any engine. By making inquiry, I found that ten mules would roll as much cane in an hour as would produce 250 gallons of cane-juice, which they boil until the water is evaporated, and the sugar produced.

"I told them that the engine-boiler might be fed with this juice, and by a cock in the bottom of the boiler constantly turning, and by taking a greater or smaller stream from it, they might make the juice as rich as they liked. In this process the juice would be so far on towards sugar, and the fire that worked the engine would cost nothing, because it would have taken the same quantity of fuel under the sugar-pans to evaporate the water, as it would in the engine-boiler.

"The steam from the engine might be turned around the outside of the furnace for distilling rum, as the distilleries require but a slow heat.

"I think the steam would answer a good purpose around the outside of the pan.

"If this method answers, the cost of working the engine would be nothing, and the engine would be then working, as it were, without fire or water.

"The Spaniards told me that if this plan answers, they would take a thousand engines for South America and the Spanish West Indies. I shall be very much obliged to you for your opinion on this business. These merchants make a trade of buying up sugar mills and pans, with every other thing they want from England, and exchange them with the Spaniards for sugar.

"At Manchester I found two engines had been made and put to work; they worked very well: three more are in building. From there I went to Derbyshire. The great pressure-engine I expect will be at work before the middle of October. A foundry at Chesterfield is building a steam-engine as a sample; two foundries in Manchester are at full work on them, and one in Liverpool. There are six engines nearly finished at Coalbrookdale, and seven in a foundry at Bridgenorth.

"I am making drawings for several other foundries. Any number of them would sell. A vast number are now being erected, and no other engine is erected where