Military tech allowed advanced further and further allowing imperial powers to use fewer resources and manpower to control large areas half a world away. Things such as magazines and better weapons made fewer men more powerful. Transportation allowed nations to distribute resources more effectively and faster using things like faster ships and laying railroads so trade and communication could be more efficient. The telegraph and better communication allowed even more isolated regions of an empire to remain in control and word to spread quickly of any problems an imperial power may have. Medical tech improved imperial powers ability to field troops in better conditions without falling to disease and empires were growing more stable and less susceptible to the catastrophic effects large populations suffered when there were epidemics or plagues. The most important advancement would be that in transportation. This is because every army depends on logistics more than training, communication meant nothing without a swift response such as when there were rebellions, and medical knowledge means nothing with proper supplies.This is all I can give you without your source of information, so all you have left to do is find evidence to support the claim. Good luck! Hope this helped.
