LAND & WATER 
September 28, 1916 
lias a second object, which is to prevent co-operation 
Octwecn the Russo-Kuunianian forces upon the north and 
the large forces which are acting from Salonika 200 
miles away to the south. If Mackensen by his ad\ance 
through the Dobrudja can secure permanently a short 
entrenched hne from the Danulx> to tht- Klack Sea and 
huld it, that advance will not ha\e been in \ain. 
A \ ery great element of strength in the holding of such 
a line is the presence of the lateral comnnmicalion already 
mentioned, the Bulgarian railway from Kustchuk on the 
Danube to Varna, which railway runs strictly parallel to 
and immediately south of the existing frontier. It 
would be no very lengthy task in such a country to lay 
lig'ht lines duwn from various rail heads upon this railway, 
wnich would ultimately afford ample communications 
with any such defensive line further north. Meanwhile, 
however, the continued possession of the Cema Voda bridge 
intact gives the Russians and Roumanians, and especially 
the former, the power to reinforce their armies in the 
Dobrudja indefinitely if sfowly, and, as their munition- 
nient incnases, to exercise a greater and greater pressure 
upon such an entrenched line. A line even 45 miles 
long would require for its continued retention, if the 
enemy connnand intends to establish a fixed barrier here, 
not less than six divisions ; and those six divisions are 
permanently lost to the Bulgarian defence against the 
Salonika armies far off to the south. It is further clear 
that the value of such a defensive line, should it be 
established, depends entirely upon the permanent pre- 
vention of a Danube crossing. It takes for granted the 
incapacity of our Ally to reach the southern shore of the 
great river anywhere between the Iron Gates and Silistra. 
To take this for grantei' the enemy must be convinced 
that for a long time at any rate he has the superiority 
in heavy artillery in this field. The Danube is an obstacle 
which, as we have seen in past articles, is absolute in 
much the greater part of its lower course through the 
presence of great belts of marshes upon the northern 
shore. But these marshes are interrupted at several 
points by hard land coming down upon either side, so 
that upon the northern and southern shores opportunities 
for departure and landing face each other. Most of these 
bridge-heads, Widin Kalafat, Lom, Corabia, Somovit, 
Turnu, Svistov and Zimnicea, Giurgevo and Rustchuk, 
Oltenitza and Turtukai. are marked by the heads of roads 
or of railways upon the Bulgarian as upon the Roumanian 
side, and there is ample opportunity for either party to 
concentrate forces in preparation for a crossing. The 
foregoing Map II. will show where these opportunities 
are to be discovered, between the Iron (iates and the 
approximate present position of the Bulgarianforces in 
the Dobrudja under Mackensen. 
But a feint upon any one or two of these points, 
coupled with a serious attempt at some other of them is 
entirely dependent, in modern conditions, upon a superi- 
ority in hea\v guns. It was the o\erwhelming superiority 
of the Austro-(;ermans in heavy guns over the Serbians 
which permitted the crossing of the Danube below Bel- 
grade last year. Even so the operation was lengthy and 
very costly. It is not true to say that it would have been 
impossible but for the Bulgarian threat in flank — it was 
already achieved before that threat had been translated 
into \igorous action. But it is true to say that but for 
the co-operation of the Bulgarian army in flank helping the 
Austro-Germansthe expense and difficulty of crossing the 
Danube would so much have hampered the latter they 
would hardly with the strength they had put in have 
succeeded in their Serbian campaign. 
Now if it was so diflicult to cross the river last year 
in spite of a crushing superiority in the number and >i/,e 
of the heavy pieces at the enemy's disposal, we can judge 
from that what the difficulty would be of either combat- 
ant now attempting a similar crossing. The good for- 
tune of a successful surprise, the gradual exhaustion of 
the enemy as time proceeds, the consequence of any really 
decisive piece of work on the Salonika front drawing 
forces thither hurriedly and sufficiently -weakening the 
northern boundary, all these between them might permit 
of a crossing of the Danube in our favour. All one can say 
is that as things stand the chances are hea\ily against it. 
and that the co-operatioaof our Allies from the north is 
still mainly dependent upon the great advantage they 
enjoy through their continued possession of the Cern'a 
Voda bridge ; an advantage which Mackensen is doing 
everything he can to counter, first by reaching it and con.- 
pelling its destruction if possible ; next, if he fails in this 
— as lie appears to have failed — by drawing a defensive 
line across the Dobrudja from the Danube to the Sea. 
Meanwhile what are the conditions of the offensive based 
upon Salonika ? What strategical problem is involved. 
The two main things that strike one on an inspection 
of this field are the way in which all the main commu- 
nications radiate from Salonika and the presence of the 
great mountain mass in the north. 
It is agreed and it is obvious that the strategical ob 
jective of the Alliance as a whole is the ConstantinopL 
