Expedition to Western Australia under Captain Grey—Excursion 328 with Auger to the north of Perth—Search for Mr. Ellis—Exploration of shores from Freemantle—Bernier and Dorre Islands; want of water; trials of the party—Water allowance reduced—A lagoon discovered—Privations and hardships of the party—Return to Bernier Island for stores—Its altered appearance—Destruction of the depôt of provisions—Consternation of Coles—Auger’s example under the circumstances—Expedition makes for Swan River—Perilous landing at Gantheaume Bay—Overland journey to Perth; straits of the adventurers—Auger searching for a missing man—Coles observes the natives; arrangements to meet them—Water found by Auger—A spring discovered by Coles at Water Peak—Disaffection about long marches; forced journeys determined upon; the two sappers and a few others accompany the Captain—Desperate hardships and fatigues; the last revolting resource of thirst—Extraordinary exertions of the travellers; their sufferings from thirst; water found—Appalling bivouac—Coles’s agony and fortitude—Struggles of the adventurers; they at last reach Perth—Auger joins two expeditions in search of the slow walkers—Disposal of Coles and Auger 1839. Services of the detachment in Spain—Last party of the 341 artillery on the survey—Survey of South Australia—Inspection at Limerick by Sir William Macbean—Triangulation of north of Scotland—Also of the Clyde—Pontoons by sergeant Hopkins—Augmentation of the corps—Also of the survey companies—Supernumerary rank annulled—Tithe surveys; quality of work executed on them by discharged sappers; efficient surveys of sergeant Doull—Increase of survey pay—Staff appointments on the survey—Responsibility of quartermaster-sergeant M‘Kay—Colonel Colby’s classes—Based upon particular attainments—Disputed territory in the State of Maine—Movements and services of the party employed in its survey; intrepidity of corporal M‘Queen—Experiments with the diving-bell—Also with the voltaic battery—Improvement in the priming wires by Captain Sandham; sergeant-major Jones’s waterproof composition and imitation fuses—Demolition and removal of the wreck of the ‘Royal George’—Organization of detachment employed in the operation—Emulation of parties—Success of the divers; labours of the sappers—Diving-bell abandoned—Accident to private Brabant—Fearlessness of corporal Harris in unloading gunpowder from the cylinders—Hazardous duty in soldering the loading-hole of the cylinder—First sapper helmet divers—Conduct and exertions of the detachment 1840.