How did the Industrial Revolution lead to the new imperialism?

The Industrial Revolution included the emergence of new military, transportation, and communications technologies that dramatically changed the global balance of power. These new technologies led directly to the new wave of European colonial conquests, and for this reason historians often call them “the tools of imperialism.”
They included breech-loading rifles; iron hulled ships; telegraph lines and underwater cables; dynamite; Maxim machine guns; light, quick-firing artillery; and smokeless gunpowder. They also included quinine treatment for malaria, which substantially diminished the mortality rate from this disease among European soldiers and in this way made it possible for them to explore and conquer the interior of Africa.
Maxim machine guns produced terrible devastation in the ranks of African forces armed mostly with cold weapons and smoothbore muskets. For example, in the key battle of Omdurman (1898) in Sudan, the British and Egyptian forces killed more than ten thousand Mahdi rebels while losing only a few dozen soldiers on their own side. Similarly, Maxim machine guns destroyed the brave Matabele warriors who fought against the British in South Africa.
Iron-hulled ships armed with guns made possible the safe and effective exploration of African interior by such waterways as the Congo River. Telegraph connections enabled European authorities to monitor developments and send help wherever and whenever it was needed.
When the Ethiopians were able to defeat an Italian invasion force in the battle of Adwa, they did so because they possessed a substantial quantity of modern weapons and had trained themselves in their use. Thus, while this was an exception it nonetheless confirmed the primary role of new industrial technology.
New weapons and means of communication likewise played an important role in colonial wars in Asia. For example, the European forces used their new technologies to defeat the Boxer Uprising in China.