Qhov zoo tshaj 1500 hnab tshos spung pw txaj, ntuj ntsuab, txiv maj phaub muaj, paj rwb thiab ntaub so noo noo. Qhov no muab ib puag ncig zoo nkauj uas muaj ib puag ncig txias thiab txawm tias pw kub.
Ntawm Rayson, txhim kho thev naus laus zis thiab kev tsim kho tshiab yog peb cov ntsiab lus zoo. Txij thaum tsim, peb tau tsom rau kev tsim cov khoom lag luam tshiab, txhim kho cov khoom lag luam zoo, thiab pabcuam cov neeg siv khoom. Lub txaj pw tsis muaj springs peb muaj cov neeg ua haujlwm tshaj lij uas muaj kev paub ntau xyoo hauv kev lag luam. Nws yog lawv uas muab kev pabcuam zoo rau cov neeg siv thoob plaws ntiaj teb. Yog koj muaj lus nug txog peb cov khoom vaj txaj tshiab uas tsis muaj springs lossis xav paub ntau ntxiv txog peb lub tuam txhab, xav tiv tauj peb. Peb cov kws tshaj lij yuav nyiam pab koj txhua lub sijhawm.Qhov khoom muaj qhov xav tau elasticity. Cov yam ntxwv ntawm cov ntaub xws li ceev, tuab, thiab xov paj ntswj yog txhua yam zoo dua rau cov ncab wardret.