Building through the Sierra Nevada Mountains was very difficult and dangerous. Temperatures were freezing during the winter and in one year alone there were 44 storms.There was the great danger of an avalanche for the men working through 18 feet of snow and camping on the tunnels beneath it. Creating tunnels through the mountains required blasting with nitroglycerin. Advancing at one foot of mountain at a time, a total of 11 tunnels was created.
He aided the americans with horses and troops i think
Research and publication of works on social and labour issue
Rome's location on the Italian peninsula, and the Tiber River, provided access to trade routes on the Mediterranean Sea. As a result, trade was an important part of life in ancient Rome. ... Later, the Roman armies used these same routes to conquer large amounts of territory and expand the empire along the Mediterranean.
I hope this helps!