At the instance of the Admiralty, a detachment of one sergeant, one corporal, and forty privates, chiefly masons and bricklayers, able-bodied men and good artificers, under Lieutenant C. Mann, royal engineers, sailed for Gibraltar in May on board the ‘Fortitude,’ and landed there the following month. The party was specially employed in constructing a cistern for naval purposes, under the military foremanship of sergeant Joseph Woodhead; and in October, 1800, it was incorporated with the Gibraltar companies. England and Russia having concluded a treaty to send an army to Holland to reinstate the Stadtholder, a corps of 12,000 men, under Sir Ralph Abercrombie, embarked for the Helder and landed on the 27th August. Attached to this expedition was a party of military artificers, consisting of one sergeant, two corporals, thirty-five artificers—seventeen of whom were carpenters—and one drummer, commanded by Lieutenant-Colonel Hay, R.E. The detachment embarked on board the ‘Amphitrite,’ and disembarking with the second division, were present in the action of that day. After forming the engineer park near the Helder, about ten men were left to repair the fort; and the remainder, divided into brigades of four to each brigade, followed the troops in their forward movement in charge of the intrenching equipment of the expedition, which was conveyed in waggons. Early in September, the detachment constructed several batteries for guns and mortars to defend the post at Zuyp; as also, subsequently, at Hoorn and Egmont-op-Zee; and to facilitate the march of the army to the latter place, they assisted in the formation of three flying bridges over canals that intersected the route. In the retreat, they were continually employed in throwing small bridges across the canals by means of planking, felled trees, and other chance materials. At Alkmaer they constructed several defensive works; and on retiring from thence, where three roads met, they raised, in an incredibly short time, a mound of earth about twelve feet high, across the junction, with the view of impeding the enemy in their pursuit of the British. None of the military artificers were killed or wounded on this service. On the evacuation of Holland in November the detachment rejoined the companies. Here, perhaps, it would be proper to allude, in a general remark, to the practice of providing detachments for foreign service. It will already have been observed, that whenever any expedition was undertaken, resort was invariably had to the royal military artificers for a selection of men to accompany it, suitable to the work upon which it was contemplated they would be employed; but the numbers furnished were always insufficient for the purpose, and no representations or remonstrances could avail in altering a custom, which, from causes not easily surmised, seems to have been pertinaciously persevered in.