ances of the time, and thus the earlier war furnishes a datum line from which we can measure the changes that have been due to the scientific progress that has been made in the intermediate period.
The novel features thus introduced into War are so many and so varied that, either in form or in substance, well-nigh everything has been changed. In 1870 neither barbed wire existed nor its remedy the Tanks. The guns then used were mainly field guns although we find associated with them a few early attempts at rapid firing by means of mechanical guns such as the French Mitrailleuse. In the late war, on the contrary, we find on the one hand both armies using in the field large numbers of guns of heavy calibre firing at long ranges and on the other hand a new war of position with its special armament of machine guns, trench mortars, Stokes guns and hand grenades, constituting a system of almost continuous hand-to-hand fighting. The old mechanically-operated quick-firing guns have now been superseded by automatic machine guns which load and fire 14
