And so the Admiral of a Fleet or Squadron hath his flag in the Main-top; the Vice-Admiral in the Fore-top and the Rere Admiral in the Missen-top, with the Crosses or Colours of their Nation and Countrymen, And thus far it is usual and common even with Fleets of Merchant men, agreeing amongst themselves for the Admiral[250] ships in this kind. In these words Boteler, writing in 1634, sums up the method of distinguishing the flags of the principal officers of a fleet which had been made possible by the appearance of the three-masted ship of war in the fifteenth century, was adopted by the English in the sixteenth, and remained in vogue until the disappearance of the sailing ship of war in the nineteenth century. But, it may well be asked, what was done to distinguish the admirals before ships had three masts? It is not easy to answer this question, for the records throw no light on it and the information vouchsafed by contemporary chroniclers is very scanty. Perhaps the answer nearest the truth would be: "nothing, for there were then no grades to distinguish." Before the sixteenth century there was rarely more than one admiral in a fleet, and on those rare occasions on which two or more admirals appear they were usually given the command "jointly and severally," that is, as co-equals[251]. In such cases it may be presumed that both, if indeed they were not embarked in the same ship, bore the St George's flag or royal standard at the masthead and were distinguished by banners of their personal arms. In the fleet that attempted invasion under Eustace the Monk in 1217, only one ship (that of the Commander-in-Chief) appears to have flown a flag at the masthead, for we are told by a contemporary chronicler[252] that one of Hubert de Burgh's men agreed, when they engaged Eustace's ship, "to climb up the mast and cut down the banner, that the other vessels may be dispersed from want of a leader." In 1346 there seems to have been still only one flag of command in a fleet. Edward III had in that year fitted out a fleet in order to make an incursion into Gascony, but after a false start which had been frustrated by contrary winds, the king, on the advice of Godefroy de Harcourt, suddenly changed his mind and set out for Normandy, taking the flag of command from his Admiral and leading the fleet himself. Et il meismes prist l'ensengne[253] de l'amiral le conte de Warvich, et volt estre amiraus pour ce voiage, et se mist tout devant, comme patrons et gouvrenères de toute le Navie[254].