Ships.
Sea transportation was just right at that time as it can carry loots, spoils of war , enough fire power to conquer new colonies, and also food and necessities for sojourners ,seafaring soldiers and traders. Even exploration of unknown territories was also done with the help of sea transportation.
Even though the revolutions did not succeed, the forces of liberalism and nationalism triumphed after 1850 because of the ideas of several individuals and artists such as Karl Marx and Gustave Flaubert. Another reason is that the people were made aware of the corrupt and deceitful actions of Napoleon III.<span />
Native Americans believe the land belongs to everyone while the Europeans believe of land ownership and claiming land for their countries.
By the time Mehmed became Sultan Mehmed II of the Ottoman Empire (1451), the Byzantine Empire was reduced to Constantinople itself, the Peloponnese, and a handful of Aegean islands. The Ottomans had had control of the territory surrounding Constantinople for decades. Mehmed fortified both sides of the Golden Horn, and would eventually lay siege to Constantinople.
Those fortifications were largely there to block reinforcements from the Black Sea, namely the Genoese in the area. In response, the Byzantines stretched a chain across the Golden Horn to keep the Ottomans from using their naval superiority to assault a section of the walls.
Some Christian reinforcements managed to get past the blockade, and Mehmed decided to make up for his navy’s failures by rolling his ships on greased logs overland, then putting them back in the water behind the chain. This rendered the Byzantines chain useless, spread their troops to defend all of the city’s walls, and made the siege much easier on the Ottomans.