Kamfanin kera kwalekwalen ya gaya muku cewa a zamanin da, mutane sun gano cewa ganye da kututturan za su sha ruwa a cikin ruwa, kuma ya gano cewa nauyin da ganye zai iya ɗauka kadan ne, kuma nauyin da gangar jikin zai iya ɗauka yana da girma. Girman gangar jikin, gwargwadon nauyin da zai iya ɗauka. kuma girma. Kamfanin kera kwalekwalen ya gaya muku cewa mutane ma sun gano cewa gangar jikin silinda ba ta da ƙarfi a cikin ruwa., zai birgima, mutane ba za su iya zama a kai ba, kuma mutane ba za su iya motsawa a kan wannan gangar jikin silinda ko kaɗan ba.
Ta wannan hanyar, mutane suna amfani da kayan aiki kamar gatari na dutse, dutse adzes, da spades don karkatar da gangar jikin bishiyar. Daga baya, an gano cewa ya fi dacewa a yi aikin itace da wuta fiye da gatari na dutse. Masu kera kwale-kwalen suna gaya muku cewa mutane suna shafa gangar jikin da wani datti mai kauri a duk inda ba sa buƙatar tono su., sannan a kona sassan da za a tono. Ta wannan hanyar, Ana kona bangaren da aka kone a cikin garwashi, sannan a yanka shi da gatari na dutse, ya fi sauki. Haka ake yin kwale-kwale.
Kamfanin kera kwale-kwalen ya gaya muku cewa akwai wani tarihi a cikin tsohon littafin kasar Sin “Littafin Canje-canje-Xixi” cewa “yanke itace jirgin ruwa ne”, wanda ke nufin cewa kwale-kwale an yi shi da itacen da aka yanke. A 1958, ya dawo muku da ku don ba da shawara na Majalisar Dinkin Duniya don, Lardin Jiangsu. A cewar bincike, sun kasance kwale-kwale daga lokacin bazara da lokacin kaka da Lokacin Jihohin Yaki. Sun kasance 11 tsayin mita, 0.9 mita fadi da 0.4 zurfin mita. Yanzu suna cikin gidan tarihin tarihin kasar Sin.
