tubular boiler in 1829.* On the occasion of its first trial, on the 21st of February, 1804, this engine drew carriages containing ten tons of bar iron for a distance of nine miles, at the rate of five miles an hour. The specification of the patent for Trevithick's steamcarriage mentions a plan for causing the wheels, in certain cases, to take a stronger hold of the ground by means of sundry rough projections, but it also adds that, in general, the ordinary structure or figure of the external surface of these wheels will be found to answer the intended purpose, which appears to have been the case in the abovementioned engine.† After making a few experiments with his engine, Trevithick forsook the locomotive for other projects of his versatile genius, and this great invention was left to be perfected and carried into general use by George Stephenson.

In the year 1809 Trevithick commenced an attempt at tunnelling under the Thames. It was the second time that this difficult undertaking had been tried, Ralph Dodd having been the first of the unsuccessful borers. When a large sum of money had been raised by subscriptions Trevithick commenced boring at Rotherhithe, and in order to save both labour and expense, kept very near to the bottom of the river; but notwithstanding the increased difficulties which he had to encounter on this account, he actually carried the tunnel through a distance of 1011 feet, and within 100 feet of the proposed terminus. At this point an unfortunate dispute arose between him and the surveyor appointed to verify his work, the surveyor asserting that the tunnel had been run a foot or two on one side. This reflection on his skill as an engineer excited Trevithick's Cornish blood, and he is said to have adopted the absurd expedient of making a hole in the roof of the tunnel at low water, and thrusting through a series of jointed rods, which were to be received by a man in a boat, and then observed from the shore. In the execution of this scheme, delays ensued in fitting the rods together, and at length so much water made its way through the gulley formed by the opening in the roof, that retreat became necessary; Trevithick, with an inborn courage, refused to go first, but sent the men before him, and his life nearly fell a sacrifice to his devotion: as he made his escape on the other side, the water rose with him to his neck, owing to the tunnel following the curve of the bed of the river, which necessarily caused the water to congregate towards one part. The work was thus ended almost at the point of its suc

*Sixth Dissertation, Encyclopædia Britannica, Eighth Edition.

† See Practical_Treatise on Railroads, &c., by Luke Hebert, London, 1837. Pages 21-4.-Mr. Francis Trevithick, who has spent considerable time in ascertaining the facts regarding his father's first locomotive, states that he has no doubt the wheels of this engine were not in any way roughed: that he has often conversed with those who made and worked the engine; that he has their copies of the original drawings; and that in all these cases he never heard or saw anything which indicated that the wheels were roughed.

cessful completion, being at once a melancholy monument of his folly and his skill.

After this unfortunate failure, Trevithick commenced many schemes; among others, his attention was directed towards the introduction of iron tanks and buoys into the Royal Navy. On first representing the importance of this to the Admiralty, the objection was raised, that perhaps, in the case of the tanks, iron would be prejudicial to the water, and consequently to the health of the crews; Trevithick was therefore requested to consult Abernethy upon the subject, which he accordingly did, and received for his answer the following characteristic reply: "That the Admiralty ought to have known better than to have sent you to me with such a question." He likewise, about this period, contributed largely to the improvement and better working of the Cornish engines, and to him the merit is due of introducing into these engines the system of high-pressure steam, and of inventing in the year 1804 the cylindrical wrought iron boiler, (now known as the Cornish boiler,) in which he placed the fire inside instead of outside, as had been the practice before his time.

Trevithick also appears to have been among, if not the very first to employ the expansive principle of steam. In the year 1811-12 he erected a single-acting engine of 25 inches cylinder at HullProsper in Gwithian, with a cylindrical boiler, in which the steam was more than 40 lbs. on the square inch above atmospheric pressure; and the engine was so loaded that it worked full seven-eighths of the stroke expansively. In this he seems to have preceded Woolf by several years. It is also stated by Mr. Gordon in his Treatise on Elementary Locomotion,' that Trevithick was the first to turn the eduction-pipe into the chimney of the locomotive to increase the draught.*

We now come to the most romantic and stirring period of Trevithick's career. In 1811 M. Uvillé, a Swiss gentleman at that time living in Lima, came to England to see if he could procure machinery for clearing the silver mines, in the Peruvian mountains, of water. Watt's condensing engines were, however, of too ponderous a nature to be transported over the Cordilleras on the backs of the feeble llamas, and Uvillé was about to give the matter up in despair, when, on the eve of his departure from this country, he chanced to see a small working model of Trevithick's engine in a shop window near Fitzroy Square. This model he carried out with him to Lima, and had the satisfaction of seeing it work successfully on the high ridge of the Sierra de Pasco. Uvillé now returned to England to procure more engines of the same kind, but he was a second time almost forced to give the matter up; for Boulton and Watt, the

Phil. Mag. and Annals of Philosophy, August, 1831, in a letter to Richard Taylor, F.S.A., by W. Jory Henwood, F.G.S.

most distinguished engineers of their time, assured him that it was impossible to make engines of sufficient power and yet small enough to be carried over the Andes. Fortunately, however, Uvillé at this point met with Trevithick himself, and was enabled to make such arrangements with him as resulted in the embarkation, during September 1814, of three engineers and nine of Trevithick's engines. On landing at Peru, Uvillé and his charge were received with a royal salute, and in due time the engines, which had been simplified to the greatest extent, and so divided as to form adequate loads for the weakly llama, were safely carried over precipices where a stone may be thrown for a league. An engine was soon erected at Lauricocha, in the province of Tarma, which successfully drained the shaft of the Santa Rosa mine, and enabled working operations to be recommenced. During the year 1816 Trevithick, hearing of this success, gave up family and fortune and embarked for South America. On landing he was received with the highest honours; all Lima was in a state of excitement, which rose to a still greater pitch, when it was found that his engines, by clearing the mines of water, had doubled their produce and increased the coining machinery sixfold. Trevithick was created a marquis and grandee of old Spain, and the lord warden of the mines proposed to raise a silver statue in his honour. All went well until the revolution broke out, when the Cornish engineer found himself placed in a very disagreeable position between the two parties. The patriots kept him in the mountains in a kind of honourable captivity, while the royalists ruined his property and mutilated his engines. Trevithick, never very patient, soon determined to end this, and, after incurring many hardships and dangers, succeeded in making his escape from the oppressive love and veneration of the mountain patriots. On their way back Trevithick and his companions encountered many perils; they had to shoot monkeys for subsistence, their clothes were almost always wet through owing to it being the rainy season of the year; they had also to ford rivers, and in many cases make their own roads by cutting down the underwood and other obstacles which impeded their progress. On one occasion Trevithick nearly lost his life; in attempting to swim across a river he became involved in a kind of whirlpool caused by some sunken rocks, and notwithstanding all his efforts he was utterly unable to swim beyond its influence, which kept carrying him round and round; fortunately just as his strength was giving way a companion, who had cut down a tall sappling, succeeded in stretching it out to his assistance, and thus drew him to land. Ultimately, after a long interval, Trevithick arrived at Cartagena, on the gulf of Darien, almost in a state of utter destitution. Here he was met by the late Robert Stephenson, who, having just received a remittance from home, lent half to his brother engineer to help him on his way to England, where he arrived on the 9th of October, 1827, bringing

back a pair of spurs and a few old coins, the sole remnants of the colossal fortune made, but not realized,' in the Peruvian mines. Before this occurred, however, Trevithick had visited various parts of the West coast of South America; part of this time he was in the company of Earl Dundonald (then Lord Cochrane), but the last four years of this period were spent by him at Costa Rica, in the countries now so well known as the route of the Nicaraguan transit and the scene of General Walker's filibuster warfare, where he projected mines and devised many magnificent schemes, but realized no permanent good for himself. Among other things, having discovered some valuable mineral deposits, he obtained from the government a grant of the land which contained them, and on his return to England succeeded, by his representations (which were confirmed by a Scotchman of the name of Gerard, who had been his companion), in organizing a company for sinking the necessary mines. Before, however, active operations were commenced, Trevithick one day entered the new company's offices to arrange finally about his own interest in the concern. A cheque for 70007. was at once offered him as purchase-money for his land in Southern America. This however was not what he had wanted, and without giving a thought to the largeness of the sum offered, he indignantly threw back the cheque across the table and walked out of the office.* After this the company broke up, and Trevithick never realized a penny-piece from his really valuable possessions in that country.

After his return from America but little is known of Trevithick; late in life he commenced a petition to Parliament, in which he asks for some grant or remuneration for his services to the country, by reason of the superiority of his machinery, stating that from the use of his engines the saving to the Cornish mines alone amounted to 100,000l. per annum; but before presenting this petition, he met with a monied partner, who supplied him with the means of perfecting his never-ceasing inventions. This was all Trevithick wanted, and the petition was consequently laid aside. Thus assisted he obtained a patent in 1831 for an improved steam engine; and another in the same year for a method or apparatus for heating apartments; and a third on the 22nd of September, 1832, for improvements on the steam engine, and in the application of steam power to navigation and locomotion. This was the last patent he took out; he died at Dartford in Kent during the following year, at the age of sixty-two.

Trevithick, by his marriage with Miss Jane Harvey, had four sons and two daughters, all of whom are still living. His manners were

*The late Michael Williams, M.P. for West Cornwall, was present during this transaction, and afterwards remonstrated with Trevithick on his folly.The cheque offered to him has been stated by one gentleman to have been for a far larger sum.

blunt and unassuming, but yet possessed a certain kind of fascination which generally secured for him, in whatever society he might be, an eager and attentive auditory. In person he was tall and strongly made, being six feet two inches in height, and broad in proportion, and to this day stories of his extraordinary feats of strength are told among the miners of Cornwall. His life remains a record of constant but brilliant failures, and that from no inherent defect in his inventions, but solely from the absence in his character of that perseverance and worldly prudence necessary to bring every new undertaking to a successful commercial issue.-Contributions to the Biography of R. Trevithick, by R. Edmunds, Jun., Edinburgh New Philosophical Journal, October, 1859.-The Land's End District, &c., with Brief Memoir of Ric. Trevithick, by R. Edmunds. London and Penzance, 1862.-All the Year Round, August 4, 1860.-And other particulars taken from original and authentic sources.

EDWARD TROUGHTON, F.R.A.S.

Born October, 1753. Died June 12, 1835.

Edward Troughton, the first astronomical instrument maker of our day, was born in the parish of Corney, on the south-west coast of Cumberland, and was the third son of a small farmer. An uncle of the same name, and his eldest brother John were settled in London as mathematical instrument makers; and as his second brother was apprenticed to the same business, Edward was designed to be a farmer, continuing to be his father's assistant till the age of seventeen.

The death of his younger brother, however, altered Edward's destination, and caused him to be placed with his brother John, at that time a chamber master, employed chiefly in dividing and engraving for the trade, and the higher branches of the art. Under the instruction of John, who was an excellent workman, Troughton made very rapid progress, and at the end of his time was taken into partnership.

About the year 1782 the Troughtons established themselves in Fleet Street, where they commenced an independant business and soon rose into eminence. After the death of his brother John, Edward alone continued the business until the year 1826, when increasing age and dislike to routine employment, induced him to take Mr. William Simms as his partner and successor.

The instruments which facilitate navigation were peculiarly ob