"The fortress of Alexandropol (40° 47' N. lat., 43° long. 45' E., 4500 feet above the sea) is situated on the left bank of the river Arpatchai, which here forms the boundary between Russia and Turkey. It is distant thirty-five miles from Kars and eighty-four miles from Tiflis. The plain on which it is situated is perfectly level and very peculiar. It has a stratum of alluvial soil for the depth of one foot six inches on the surface, and then a substratum of fine uniform lava, ten to fifteen feet thick, supposed to have issued from Mount Alagos (13,450 feet), an extinct volcano thirty miles from Alexandropol. The depth of the earth allows the growth of grain, but entirely prevents that of trees, which with their roots cannot penetrate into the lava. The Russians have taken advantage of this bed of lava in the ditch of the fortress. The fortress is well constructed and in perfect repair. There are upwards of 200 guns (varying from 36-pounders to 12-pounders) mounted on the works, and about 100 in reserve, of which 30 are field-guns with their equipment wagons, etc. The garrison would be 5000 to 6000, including artillery. There are large supplies of ammunition and military stores. The ditch, twelve feet deep, of the two western fronts has not been excavated near the flanks on account of the expense. The Russians have constructed in the centres of the two curtains a _caponnière_ with two guns in each flank to defend the dead angles caused by the non-excavation of the whole of the ditch. In the centre of these two fronts is a large _caponnière_, mounting ten guns in the upper tier and eight in the lower tier. This _caponnière_ is on a lower level than the enceinte of the place. The counterscarp at the north-west and south-west angles of these two fronts is for the distance of twenty yards composed of a crenellated wall four feet six inches thick. This was caused by the irregularity of the ground. The bomb-proof barracks of the northern fronts mount in casemate two tiers of fourteen guns at the curtains. The flanks have five guns in casemates open to the rear, in addition to the guns on the parapet above. The lunette in the ditch is eight feet deep. The eastern front has an escarp fourteen feet high cut in the lava, and well flanked by the _caponnière_ defending the entrances, mounting four guns. The bomb-proof barracks in the northern fronts have one tier of eight guns in casemate at the curtains, and three guns in each flank in casemates open to the rear. The two outworks are closed at the gorge with a loopholed wall, flanked by a small guard-house. They have no ditches, but an escarp of ten feet in the lava. The tower marked _A_ in my plan is sixty yards in diameter, with a well in the centre.