<P> The edge of a pagoda 's eaves forms a straight line , with each following edge being shorter than the other . The more difference in length ( a parameter called teigen ( 逓減 , gradual diminution ) in Japanese ) between stories , the more solid and secure the pagoda seems to be . Both teigen and the finial are greater in older pagodas , giving them a sense of solidity . Vice versa , recent pagodas tend to be steeper and have shorter finials , creating svelter silhouettes . </P>
the reason japanese pagoda roofs decline in size is
the more solid and secure the pagoda seems to be