A daring nighttime sally by a handful of troops under Maj. Andreas Trimbach on the evening of the 17th succeeded in storming the leading saps of the Waldrecker second parallel and detonating a bundle of howitzer shells at the entrance to the main mining gallery of the Waldreck engineers. An unknown number of Waldrecker miners and engineers, along with numerous impressed Dolmen labourers, are believed to have been at work in the galleries below, and are now believed to have been trapped by the detonation.
Approach to the Waldrecker siegeworks seems to have been accomplished by a countergallery terminating near the second parallel, fired at the same time as the detonation of the Waldrecker mines. The approach to the Waldrecker works was aided by the nearly moonless night, coupled with the dense night fog following the thunderstorms which pounded the area over the preceding days. Rescue efforts by other Waldrecker engineers and miners are now underway, but the extent of the collapse achieved by Maj. Trimbach's raid is still being determined.
In spite of this notable success by the defenders of Dolmen, the work of the Waldrecker siege guns has been continuous and merciless since their siting in the first parallel, silencing the guns of the opposing bastions in the first two days, and commencing the pounding of the Bastion Gertrude and the demilune adjacent to it and Bastion Magdalene, suggesting that the Waldrecker plan is to storm the demilune as a precursor to an assault on Bastion Gertrude. Hastily constructed traverses along the adjoining curtains have limited the effect of ricochet fire, but the overwhelming superiourity of the Waldrecker guns makes the obliteration of those defences merely a matter of time.
The completion of the Waldrecker second parallel is imminent, and the movement of guns into firing pits along those new works is expected this week, in spite of the raid. The movement and disposition of the main body of the forces of Duke Ignaz remain obscure, but the prolongation of the defence of Festung Dolmen beyond the end of the month seems unlikely, even in light of the valiant intrepidity in defence of the works by the officers and men under Maj. Trimbach's command.
The reader is invited to consult http://sunearth.gsfc.nasa.gov/eclipse/phase/phases1701.html for more details describing astronomical conditions of the 18th century.