Given the task definition and input, reply with output. This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.

His opponents learned from Napoleon's innovations. The increased importance of artillery after 1807 stemmed from his creation of a highly mobile artillery force, the growth in artillery numbers, and changes in artillery practices. As a result of these factors, Napoleon, rather than relying on infantry to wear away the enemy's defenses, now could use massed artillery as a spearhead to pound a break in the enemy's line that was then exploited by supporting infantry and cavalry. McConachy rejects the alternative theory that growing reliance on artillery by the French army beginning in 1807 was an outgrowth of the declining quality of the French infantry and, later, France's inferiority in cavalry numbers. Weapons and other kinds of military technology remained largely static through the Revolutionary and Napoleonic eras, but 18th-century operational mobility underwent significant change.
Who learned from Napoleon's innovations?