In the night of the 6th to 7th, the first parallel was opened, and the construction of the redoubts necessary for safety began. This work was only interrupted by the batteries, the fire of which was turned upon the new redoubts from the beginning of their construction. The same night an end of a parallel with a flying sap was opened to support a battery which served the double purpose of disturbing the advanced redoubt on the right of the besieged and of driving off the ships of war which might have taken the left of the great attack in reverse. This work, information of which was given by a deserter, was greatly troubled by the batteries of the besieged, and the attention which they paid to it diverted their attention from the opening of the great attack. _October 7th._--At daybreak the guard batteries entered the parallel. From the 7th to 8th the perfectionment of the first parallel and the redoubts was continued, and the construction of the batteries begun. The nature of the ground on the left decided their establishment behind the parallel, and one was placed on its left flank beyond the ravine. _October 8th._--At noon the parallel and the battery at the left attack were completed. From the 8th to the 9th the perfectionment of the parallel, and of the redoubts and batteries was continued, and communications opened in their rear. _October 9th._--The construction of a battery of mortars was begun in part of the parallel. In the afternoon the batteries began their fire, and subdued that of the enemy. The fire of that on the left compelled the frigate and the other vessels of war to withdraw. From the 9th to the 10th the perfecting of the works was continued, and palisades were set in the ditches of the redoubts. On the left attempts were made to set fire to the abattis of the redoubt. ENGINEERS’ JOURNAL OF THE SIEGE OF YORK. * * * * * [Illustration: _Plan of the SIEGE of_ YORK TOWN in Virginia.] _This map of the siege of Yorktown appeared in the London edition of Tarleton’s_ Campaigns, _1787. The cartographer has not been identified, but was probably with the British Army during the siege. The British and allied entrenchments are clearly shown, with the allied encampments in rear of the latter._ 7. THE BOMBARDMENT Some of the allied batteries were ready to fire by the afternoon of October 9. All movements and activities up to this time had been merely preliminary. The siege of Yorktown now settled into deadly earnest, with a heavy and continuous bombardment of the British position. Additional batteries took up the chorus on the following morning. Surgeon Thacher, of the American Army, in the intervals of caring for the wounded, watched the terrible spectacle.