Alexander Dyce, A General Glossary to Shakespeare's Works

corporal “of his field—A,” LOVE'S LABOUR'S LOST, iii. 1. 177. “Dr. Farmer's quotation of the line from Ben Jonson [New Inn, act ii. sc. 2], ‘As corporal of the field, maestro del campo,’ has the appearance, without perhaps the intention, of suggesting that these officers were the same: this, however, was not the fact. In Styward's Pathway to Martiall Discipline, 1581, 4to, there is a chapter on the office of maister of the campe, and another on the electing and office of the foure corporalls of the fields; from which it appears that ‘two of the latter were appointed for placing and ordering of shot, and the other two for embattailing of the pikes and billes, who according to their worthinesse, if death hapneth, are to succeede the great sergeant or sergeant major,’” (DOUCE) . “Corporals of the Field. This office is a place of good reputation, though of great paines, labour, and industry. There are commonly four of them, of which two are alwayes attending on the marshall or generall, as their right hands, discharging by their endurances the governours of the campe of many travailes, cares, and watchings. They ought either to be ancient captaines, casheer'd as we say in the altering and changings the list of the army; or experienced souldiers that know how to bestowe the companies, and where to order the regements and ambuscadoes; but in no case they must be chosen either for favour or affection, because their service consists in knowledge and understanding the secrets of the warre, as having the overlooking of the colonels and captaines companies, that they march in order; the informing of the quarter-masters what squadrons shall goe to the watch, or other imployments; the giving the alarums to the campe, as taking notice of the scowt-master's direction; the acquainting the colonell of the regiment volantem with any danger or busines; the overseeing of skirmishes, and so to certifie the marshall and sergeant-major where is any defect or neede of supply; and a continuall attending both night and day, as never out of imployment, when the enemy lodgeth neare, or any towne or place is besieged.” The Military Art of Trayning, 1622 (cited by Mr. Halliwell).