‘The longer the ladder the easier the feat would be; I’ll tell you why presently.’
‘If the centre of gravity is in our body or chest, how do we manage so easily to stand upright? My sister has a wooden doll which won’t stand up at all.’
‘That doll has no muscles in her feet. You have; and even when you are standing still those muscles are constantly at work, controlling the body so as to keep the centre of weight directly above the feet.’
‘I don’t feel them working.’
‘No; you are so used to it. But balance yourself on one foot. Do you feel the muscles now?’
‘Yes; they are constantly at work. Try it, all you boys.’
All the boys tried it; and very comical they looked standing in a row on one leg and swaying about in their efforts to keep the balance. The centre of gravity was in each case supported, though there was not much gravity in their faces. That is not the right place for ‘gravity’ at playtime.
‘Steady!’ cried their teacher, ‘you are swaying about like the unhappy Greek! Why do you throw out your arms, first to one side and then to the other?’
‘To keep the balance, sir.’