Interesting video from The Great War channel on YouTube.
Outlines the development of pre war artillery for France, Germany and Britain in relation to their doctrine.
France - Canon de 75 modele
Germany - 7.7cm Feldkanone 96 / 10.5 cm Feldhaubitze / 42cm Krupp "Big Berthas"
Britain - QF 18 pounder gun / BL 60 pounder gun / QF 4.5 inch howitzer / 9.2 inch heavy siege howitzer