Fortunately, the newly-appointed generals soon arrived, and with great alacrity betook themselves to the task of reform. General Gates, who was versed in the details of military organization, exerted a powerful influence in this salutary work. In a short period, the camp presented an improved aspect. The soldiers became accustomed to obedience; regulations were observed; each began to know his duty; and, at length, instead of a mass of irregular militia, the camp presented the spectacle of a properly-disciplined army. It was divided into three corps: the right, under the command of Ward, occupied Roxbury; the left, conducted by Lee, defended Prospect hill; and the center, which comprehended a select corps, destined for reserve, was stationed at Cambridge, where Washington himself had established his head-quarters. The circumvallation was fortified by so great a number of redoubts, and supplied with so formidable an artillery, that it had become impossible for the besieged to assault Cambridge, and spread themselves in the open country. It was believed, also, that they had lost a great many men, as well upon the field of battle as in consequence of wounds and disease. Another material deficiency was the want of gunpowder. In the depositories at Roxbury, Cambridge, and other places, there were found to be only ninety-six barrels; the magazines of Massachusetts contained but thirty-six more; and, after adding to this quantity all that New Hampshire, Rhode Island, and Connecticut could furnish, the amount fell short of ten thousand pounds, which allowed only nine charges to a man. In this scarcity and danger, the army remained more than fifteen days; during which time, had the English attacked them, they might easily have forced the lines, and raised the siege. At length, by the exertions of the committee of New Jersey, a few tons of powder arrived at the camp, which supplied for the moment the necessities of the army, and averted the evils that were feared.