Mr Brunei on a New Plan of Tunnelling, calculated 
Art. XII.— a New Plan qf Tunnelling, being calculatedjor 
opening a Roadway under the Thames. By M. J. Brunel, 
Esq. F. R. S. Civil Engineer. With a Plate. 
J^S the celebrated author of this plan has had the kindness to 
favour us with a description and drawings of his new method of 
tunnelling, which, though printed, are we believe not intended 
for separate publication, we conceive that our readers will be 
highly gratified by an explanation of a method which, in point 
of ingenuity and utility, has not been surpassed by any of our 
modern improvements in the useful arts. 
The writer of this notice, had the peculiar gratification of 
examining, in 1818, in company with his much respected friend 
Professor Pictet, all the original drawings, on a large scale, at 
the house of Mr Brunei, and of having them explained by 
that distinguished engineer. Mr Brunei then mentioned that 
the idea upon which his new plan of tunnelling is founded, was 
suggested to him by the operations of the Teredo, a testa- 
ceous worm, covered with a cylindrical shell, which eats its way 
through the hardest wood ; and has, on this account,' been called 
by Linnaeus Calamitas Navium. The same happy observation 
of the wisdom of Nature, led our celebrated countryman Mr 
Watt to deduce the construction of the Flexible Water Main, 
from the mechanism of the lobster’s tail 
“ The difficulties,” says Mr Brunei, “ which have opposed 
themselves to every attempt that has been hitherto made to exe- 
cute a tunnel under the bed of a river, have been so many and 
so formidable, as to have prevented its successful termination in 
those instances where the attempts have been made. 
To propose, therefore, the formation of a tunnel after the 
abandonment of these several attempts, may appear somewhat 
presumptuous. On inquiring, however, into the causes of failure, 
it will be found that the chief difficulty to be overcome, lies in 
the inefficiency of the means hitherto employed for forming the 
excavation upon a large scale. 
In the case of the drift-way made under the Thames at Ro- 
therhithe in 1809, the water presented no obstacle fpr 930 feet ; 
* See this Journal, vpl. iii. p, 60. 
