bank is for
the most part marshy, and is dominated by the southern bank. The German
strategist, von Moltke, who knew Turkey well, and had written the best
history of the Russo-Turkish War of 1828, maintained that the passage of
the Danube must cost the invaders upwards of 50,000 men. Thereafter,
they would be threatened by the Quadrilateral of fortresses--Rustchuk,
Shumla, Varna, and Silistria. Three of these were connected by railway,
which enabled the Turks to send troops quickly from the port of Varna to
any position between the mountain stronghold of Shumla and the riverine
fortress, Rustchuk.

Even the non-military reader will see by a glance at the map that this
Quadrilateral, if strongly held, practically barred the roads leading to
the Balkans on their eastern side. It also endangered the march of an
invading army through the middle of Bulgaria to the central passes of
that chain. Moreover, there are in that part only two or three passes
that can be attempted by an army with artillery. The fortress of Widdin,
where Osman Pasha was known to have an army of about 40,000 seasoned
troops, dominated the west of Bulgaria and the roads leading to the
easier passes of the Balkans near Sofia.

These being the difficulties that confronted the invaders in Europe, it
is not surprising that the first important battles took place in Asia.
On the Armenian frontier the Russians, under Loris Melikoff, soon gained
decided advantages, driving back the Turks with considerable losses on
Kars and Erzeroum. The tide of war soon turned in that quarter, but, for
the present, the Muscovite triumphs sent a thrill of fear through
Turkey, and probably strengthened the determination of Abdul-Kerim, the
Turkish commander-in-chief in Europe, to maintain a cautious defensive.

[Illustration: MAP OF BULGARIA.]

Much could be said in favour of a "Fabian" policy of delay. Large
Turkish forces were in the western provinces warring against Montenegro,
or watching Austria, Servia, and Greece. It is even said that
Abdul-Kerim had not at first more than about 120,000 men in the whole of
Bulgaria, inclusive of the army at Widdin. But obviously, if the
invaders so far counted on his weakness as to thrust their columns
across the Danube in front of forces that could be secretly and swiftly
strengthened by drafts from the south and west, they would expose
themselves to the gravest risks. The apologists of Abdul-Kerim claim
that such was his design, and