492 
POSEN AND STKASBURG. 
outside the glacis, and passes into it to the one and only station. Here is, 
no doubt, a certain amount of the framework for a complete system of 
military railway communication—requiring, however, considerable additions 
before it can be reckoned fit for regular work. And, as a post of obser¬ 
vation and signals, the spire and towers of the cathedral may not be left out 
of mention: they offer, from a height of 450 ft. downwards, various con¬ 
venient stations little obnoxious to hostile fire; and it is worthy of note 
that during the last siege the garrison was able to maintain its employment 
of them to this purpose until the end. 
Remarks. 
The particulars of the additional works designed to adapt these two 
fortresses to the necessities of the present-day defence—actually, for the 
most part, applied in the case of the older one at Strasburg, and in course 
of application to the very recent one at Posen—are similar in character; 
only in degree, there is more provision for the intercommunication and 
mobility of the defenders, and more distinct shallowness in the trace of the 
individual forts, promised in the later instance. As to the general purpose 
of these chains of detached forts, though it may remain open to question 
whether they, in the present instances, absolutely preclude an effective bom¬ 
bardment of the body of the place as long as they remain effective, yet it is 
evident that as fortified camps they constitute most influential strategic 
positions; and, moreover, that the body of the place must remain free from 
serious attack until after their reduction. As to their particular strength, it 
would seem that the regular attack must find very great difficulty in 
applying to them the old-established processes of enfilade, counter-battering, 
or breaching fire, owing to their flatness of trace, massive and lofty traverses 
and unbroken parapets, narrow ditches and sunk escarps: nor would the 
more modern expedients of vertical and of curved fire work at their most 
telling and satisfactory rates, on account of the same limiting conditions: 
mining would, then, become the most suitable resource, or accessory measure, 
for the besieger to bring into play; but to this process also—however 
surely ruinous eventually to the defence, if pushed perseveringly home— 
some basis of hindrance and opposition is already prepared in the roomy 
counterscarp galleries and the undeclared extensions therefrom: and as 
these forts are, moreover, susceptible of intimate support, according to the 
urgency of the occasion, from their flanks and rear, and remain always open 
to reinforcement by an active garrison, they appear to offer to the attack a 
more difficult and uncertain task than did the more continuous but less 
apposite strength of previous systems. 
In the two examples here exhibited, we see, of the new style, simply those 
additions which have been thought necessary to the present completion of 
certain fortresses formerly completed according to older styles; but not the 
whole system of fortification which might be adopted in case of devising a 
fortress radically, from the very beginning, to meet the requirements of the 
present day. The relative proportions of the total strength to be put into 
the detached forts and into the body of the place must vary according to 
the nature and purpose of the fortress, as well as to the features of the 
ground. Thus, a small fortress, intended merely to command a certain line 
