Hence, an early ideograph for gai was com-posed of a 'silk' radical and 'bamboo' elements; it later evolved into what appears to look like an opened umbrella.
工藝家們推測，「蓋」最早多用絲質材料做覆面，竹子做支架，因此傘的原小篆字形為「」，部首為「絲」，後來才以張開形象繪之，形「」。