SYNOPTICAL CHARTS. 
477 
Before referring in detail to any of the columns referring to the 
evolution of Artillery, I would ask you to notice two broad horizontal 
bands of shade, commencing respectively in the latter part of the 
fifteenth and nineteenth centuries. 
These two bands of shade mark the two most important, epochs in 
the history of fortification and artillery since the invention of gun¬ 
powder. A large number of important inventions occur in each 
epoch; but in each case, one improvement stands out as pre-eminent¬ 
ly the leading invention of the time. 
The earlier period may be called the epoch of cast-iron shot, the 
period in which we are now living the period of rifled ordnance. 
Each of these great inventions has profoundly modified the theory 
and practice of fortification, as regards trace, profile, and material 
used. These changes are noticed graphically, or are entered in the 
form of notes in the fortification columns on the left of the chart. 
As a specimen of one of the artillery columns, let us now take the 
one descriptive of a typical siege piece from the time of Henry VIII. 
down to the present day. 
The subject is divided up under three headings, the column on the 
left referring to the variation in weight of a typical siege piece, the 
second column showing the variation in muzzle energy,, and the third 
the variation in the effective breaching range. 
This triple division of the subject was suggested by the following 
sentence from Bacon’s Essay on the “ Vicissitude of Things,” pub¬ 
lished in 1625 : — 
“The conditions of weapons and their improvements are: First 
the fetching afar off; for that outruns the danger; as it is seen in ord¬ 
nance and muskets. Secondly, the strength of the percussion, where¬ 
in likewise ordnance do exceed all arietatious and ancient inventions. 
The third is, the commodious use of them, a^s that they may serve in 
all weathers; that the carriage may be light and manageable, and the 
like.” 
The column on the left shows that the “ commodious use ” of a 6- 
inch howitzer is greater than that of a “ culverin ’ of the time of Henry 
VIII. The weight of the latter piece—a 20-pr.—is seen to be 43 
cwt.; whereas the former—a 120-pr.—weighs only 30 cwt. 
Each of these pieces may, I think, be fairly taken as the typical 
siege piece of its period; in other words the number of “ culverins ” 
employed at any siege during the reign of Henry VIII. probably as a 
rule exceeded the number of heavier pieces such as “ demi-cannons,” 
“ cannons,” or “ great curtals,” or of lighter pieces such as “ sacres ” 
or “ demi-culverins ” ; and at the present day, the number of 6-inch 
howitzers would probably show the same pre-eminence. 
As a matter of historical fact, the 24-prs. of Peninsular and Crimean 
times were numerically preponderant in the siege trains used before 
Badajos and Sebastopol 
The second column shows how “ the strength of percussion,” to use 
Bacon’s phrase has increased from about 89 foot-tons—the muzzle 
energy of a “ culverin ” of Henry VIII’s time—to 505 foot-tons—the 
