THE FORTH BRIDGE. 



419 



this amount of H.P. at work would be a mere fraction of the working 

 expenses of the tunnel, which, for many reasons, should not be as heavy 

 as those of other lines. 



COMPAEATIVE TABLE 



Showing the Principal Divisions of the Chalk accobding to 

 English and French Geologists. 



Chalk without Flints. 



Chalk with Flints. 



• 



Craie de Rouen. 



Craie Moyenne. 



Craie Superieure. 



Scale for Comparative Table. 



III! 



100 



200 



300 



iOO 



500 



600 



700 



800 feet. 



The Forth Bridge. By B. Baker, 



[A comniiinication ordered by the General Committee to be printed in extenso 



among the Reports.] 



[Plate Vin.] 



At the request of Dr. Siemens the following short paper on the proposed 

 Forth Bridge has been prepared, though the author himself would have 

 preferred to postpone any communication on the subject to the British 

 Association until the works were well in hand, and the many points of 

 interest and difficulties inseparable from so gigantic an undertaking had 

 manifested themselves. At the present moment a commencement has 

 not been made, the whole period, from the revival of the project last year 

 until now, having been occupied in the necessary preliminary work of ob- 

 taining the Act of Parliament and preparing the designs and specifications. 

 It is believed, however, that in a few weeks the contract will be let, and an 

 energetic start will at once be made with the works. 



E E 2 



