It is possible to float a house like a s...

It is possible to float a house like a ship on a sea oí mud, if only enough concrete be spread round to keep the moist foundation from rising round the walls; or whole cities may be built on piles in a peat bog, like Venice or Amsterdam. A foundation of slipping clay can be kept in place on the side of a hill by a drain above the clay bed, and so keepin? it dry and stationary; and a house built on sand is often as firm as another on a rock.