That work was the purchase of medicines--chiefly morphine and quinine--and the smuggling of them through the lines into the Confederacy for the use of the armies there. For it is one of the barbarisms of war which civilisation has not yet outgrown, that medicines, even those which are imperatively necessary for the saving of life and the prevention of suffering, are held to be as strictly contraband as gunpowder itself is. Agatha's plan was to have her associates in Baltimore purchase medicines and surgical appliances in that city and elsewhere--buying only in small quantities in each case, in order to avoid suspicion, but buying large quantities in the aggregate--and forward them to her in Virginia by way of her underground railroad; that is to say, passing them from hand to hand over the route by which she had herself reached Baltimore. Having perfected these arrangements, her next task was herself to get back to her home, whither she did not mean to go empty-handed. She had gowns made for herself and Martha, using two thicknesses of oiled silk as interlining. Between these she bestowed as much morphia as could be placed there without attracting attention. This done, she was ready for her return journey, which presented extraordinary difficulty. She could not return by the way she had come, lest the purpose of her journey should be discovered, and her plans for the future be thwarted. She must find some other way. At first she thought of making her way southward to the lower reaches of the Potomac, and depending upon chance for means of getting across the river there, but this was rendered impracticable by the news that the Confederates had retired from their advanced outposts to Manassas and Centreville, with the Fairfax Court-house line as their extreme advance position. This meant, of course, that they no longer held in any considerable force the posts along the lower river. Moreover, Agatha learned that both the Potomac below Washington, and the navigable part of the Rappahannock were closely patrolled now, by night and by day, by a numerous fleet of big and little Federal war-ships. There seemed no course open to her but to try in some way to get through to Stuart's pickets, if in any way or at any risk she could manage that. That she determined to attempt.