A JOURNAL OF THE Siege of : IN A LETTER from an Officer in the Town; Dated May 18. 1689.  
Licenced and Entered according to Order.  
ON the 23d of April (St. George's Day) we discovered a great Body of Foot, about a mile from the Town; which we imagined to be the Van of the Enemy's Army; but they presently wheeled to the Northward; and settled before the Castle of Kilmore, which they furiously Attacked for the space of Three Hours; and at last (the Walls being old and ruinous, and the place not tenable) the Garrison yielded upon Articles, which were not well observed. They Posted there 500 men, and immediately marched to join the Body of the Army, about Four miles from Derry.  
On the 24th our Scouts discovered the whole Army under march in three Lines towards the Town. They judged them about Forty Battalions of Foot, and Ten Squadrons of Horse.  
About Three of the Clock that Day, the whole Army came up within a mile of our Walls; lying in length from the River to the little Hill of Ferrick: All that Day, and the 25th, they were busied in settling their Quarters.  
On the 26th they drew a Line of Contravallation from the River to the Hill.  
On the 27th their Line was finished.  
On the 28th they advanced with a Body of 400 Horse within Musket shot of the place, to view the Ground, upon whom we sallied with a thousand men, Horse and Foot: the Dispute was sharp for the space of half an hour: the Enemy lost the Lieutenant-General Mamoone, two Colonels, six Captains, eight Lieutenants, and about sixty Musqueteers; but a great body of the Enemy's Horse coming to sustain their Party, we drew off under the Fire of the Walls: We lost about 100 Soldiers, and an excellent Officer, Colonel Marlin, two Captains, and four Lieutenants.  
On the 29th, about Eleven at Night, Major-General Loci, With Eight Battalions, advanced within 200 Paces of the place, we firing very furiously upon them, and they at us. About Two in the Morning we perceived the Enemy were covered in the Ground, and having made a large Lodgement on the 30th at Night, they worked very hard, and made small fire; so they advanced the main Attack that Night Thirty Paces.  
On the 1st. of May, about Eleven at Night, we made a small Salley with 400 Men, to discover the Enemy's Posture; but the Officer who commanded that Sally, after Two or Three Discharges, in great disorder retired Cowardly to the Town; for which base Action, the next Day he was Tried by a Council of War, Condemned, and Shot at the Mainguard.  
On the 2d we Sallied forth with 500 Men, about Twelve at Night, and having taken the advantage of the Ground, Posted behind a Ditch Bank, we continued our Fire upon the Enemy till about Three, in the Morning.  
On the 3d we rested in the Town quiet, and the Enemy working very hard, advanced Forty Paces.  
On the 4th in me Morning, we perceived the Enemy had branched their main Trench into Two Attacques, the one pointing to Colraine Gate, and the other towards the Water-gate; and had also set forth the Ground for a Battery betwixt the two Attacques.  
On the 4th at Night, the Battery was finished, and Five small Pieces planted, it not being possible to bring up the heavier Guns.  
On the 5th, being the Lord's day, we rested; but that Night, the Enemy's working without disturbance, made great advance, and drew a Line of Communication betwixt the Two Attacques, which served also for a Line of Defence before the Front of the Battery.  
On the 6th. All day the Enemy's Guns stood smartly against the Walls; in which we discovered a Crack from the Round-Tower to the little Redoubt.  
On the 7th at Night we Sallied with 700 Men; but finding the Ground levelled, under which we before were sheltered, after an Hour, having in vain attempted to force the Enemy's Trenches, we retired to the Town.  
On the 8th the Enemy advanced their Attacques within Ten Paces of the Ditch; we continually firing on them from the Walls.  
On the 9th, they made a large lodgement on the Bank of the Ditch.  
On the 9th, with Faggots, Boughs, and other materials, they filled the Ditch, throwing in Earth, making a passage for a Front of Fifteen Men.  
On the 11th, they made a covered way cross the Ditch, to the Foot of the Walls.  
On the 12th, Colonel Walker beat a Parley, and desired a Cessation of Arms for that day, to keep or solemnize the Sabbath, which was agreed; that day, Colonel Walker preached, taking for his Text, The Sword of tit Lord, and of Gideon: He exhorted the Soldiers to be of good Courage and Resolution, telling them, That on their Valour relled the safety of three Kingdoms, and bid them be ready for some great Action.  
On the 13th, At night the Miners began to work at the foot of the Wall, but we gave them great disturbance with Granadas, Stones, Fire, hot Water, and the like.  
On the 15th, We perceived the Miners were lodged under the Wall.  
On the 16th, The whole Garrison was commanded to be ready by ten a Clock at night: About eleven we marched forth at Colraine Gate 7000 Men, leaving 1500 for the Guard of the Town; we posted 1000 Men on both sides The hollow way, to secure our Retreat, and marched with 6000. in two Lines towards the Enemy; at our approach, we received three discharges from their Trenches, but Colonel Walker gave order that no Man should fire a Gun, till we came within half Pistol-shot of the Trenches; when doubling our Ranks, we poured in upon them three Volleys of Shot, at which they began to shrink; but their Officers again putting them in order, they sustained our fire for half an hour, after which they began to retire, but in good Order; and marching cross the Front of the Batterry, joined the Attack on the side of the Water-gate. We found difficulty to cross the Enemy's Trenches, in which time the Guns of the Battery being turned against us, made Three Discharges with Great and Small Shot, and caused great Slaughter amongst our men; but having passed the Trenches, we carried the Battery without Resistance; and so Marched to Attack the Enemy on the side of the Water-gate, where we found them very strong, and disputed every Foot of Ground with great Courage and Conduct; but after an Hours Firing very hotly on both sides, they marched in good order down their Trenches towards their Camp, firing upon us as they went, and we on them, and left us Matters of their Trenches, Cannon and Battery. We stood under Arms till Three in the Morning, when sending forth Scouts, they discovered the Enemies were drawn up in Battalia, in Five great Bodies along their Line. An Hour after we sent again, to discover their Posture; and they brought us word, That they perceived their Carriages were marching off: We called a Council, Whether it were convenient to follow them; but considering that our men were extremely tired, we thought it fit to remain quiet, and defend the Posts we had gained, than hazard our Men upon so dangerous an Enterprise: About Three in the Afternoon, their whole Army disappeared, being withdrawn Four Miles from the Town. We lost 500 men, and nigh 1200 wounded; we found of the Enemies 4000 dead in the Trenches. We are now filling the Trenches, and ruinating their Works.   

London: Printed for Richard Chiswell, at the Rose and Crown in St. Paul's Churchyard. 1689.