Seismograph's drum feel the seismic waves. There is a weight that moves the pen so that when the seismic waves are felt, the pen jiggles and records it on paper.
Answer:
Wetlands are places which contain more moisture content than the arid or dry land. It is believed that the wet region have less strength . As we all know anything which is in contact with water have lesser strength due to water molecules harm the chemical bonding in the object.
Ancient times house construction was done using natural rocks and stones and which reacted using physical bond hence the ancient people were successful as it used physical reaction and hence its strength was not affected by the moister. Present day homes are built using chemical bonds which told two layers adhere hence moisture affect its strength and binding.
Colonize Africa or South America to settle more colonies there
