He studied the fossils' age and how tall the mountains are. He also studied how old they are. I don't know about Coal Beds but he also used balloons to find out the continents were once a big supercontinent called Pangaea and they apparantly drifted apart
The Columbian Exchange had positive and negative consequences.
Some of the positive consequences were the introduction of different nutrients and food supplies into the Old World, such as corn or potatoes. This improved the diet of most Europeans, leading to a population growth in the next generations.
However, Europe benefited more than the Americas, for some of the negative consequences about the Columbian Exchange were the introduction of diseases into the continent and the slavery of African populations into the Americas.
Their thoughts can't be hundred percent sure without the diaries but they had thoughts on how much hardship they would have to go through the trip across mountains and rocky paths, they also had to survive with minimal resources, so their thoughts on this was probably brave and rough trip, they had no clue if they were gonna survive or what was gonna happen, they territory was unknown.
Through slab-pull and ridge-push.
hope this helps!
<span>"I was the very first Roman Emperor, ruling with absolute power until I was assassinated at the Roman Senate." = JULIUS CAESAR (although technically he was Dictator of the Roman Republic rather than taking the title "emperor").
"I was a Roman Emperor who was rumored to have started the Great Fire of Rome but instead I used it as an excuse to persecute Christians." = NERO
"According to legend, my brother and I built the city of Rome until we fought over its name so I killed him." = ROMULUS
"My great uncle was Julius Caesar so I hunted those responsible for his murder, was the first emperor to take the title 'Caesar,' and am credited with bringing about the Pax Romana." = CAESAR AUGUSTUS
"I was a Roman Emperor who 'defeated' the god of the sea Neptune, collecting seashells as my prize, and threatened to make my horse a Consul of Rome." = CALIGULA
"I was a Roman Emperor who persecuted Christians and decided that the best solution to Rome's problems was to divide it into An Eastern Empire and a Western Empire." = DIOCLETIAN</span>