Even science cannot escape the fascination. The brilliancy and nearness of the moon and her many recurring changes all aid in fixing the attention of science. Modern and ancient science alike unite in watching the night's great light as she performs her journey round us. Nations regulate themselves and their acts, religious and commercial, by the moon. Feast days of the church are fixed more by the lunar than the solar calendar, for all the movable feasts depend on the moon.
Calendars rule commercial affairs in credits, obligations, and settlements.
From earliest times the calendar, ruled in fact by the moon's motion, has been of immense interest to man. Periodically rulers of the earth try to reform the calendar of days and months when it as periodically gets out of order. And when the present style of reckoning was introduced, many communities of men in Europe rebelled because they thought they had been deprived of some actual days of life. Caesar ordered a reformation of the calendar by attempting to use the sun, but in time it fell into great confusion. Pope Gregory XIIl directed ten days to be suppressed, and then found that the Julian calendar had an error which would amount to three days in four hundred years - quite a serious matter.