John Hawkins thiab Sampson Mordan Thawj Patent Tus Mechanical Pencil. Silver S. Mordan & Co txhua yam cwj mem nrog cov cim rau 1825.
Thaum twg yog tus cwj mem tshuab tsim tawm?
Silver S. Mordan & Co txhua yam cwj mem nrog cov cim rau 1825.
Thaum twg cov xaum siv tshuab tau tsim tawm?
xaum nyob rau hauv 17th Century Xyoo 1662, thawj cov xaum tsim tawm tau tsim nyob rau hauv Nuremberg, lub teb chaws Yelemees.
Vim li cas cov xaum ntoo zoo dua li tshuab?
xaum ntoo yuav tsum tau siv zog ntau dua rau kev ua haujlwm ntev dua thiab khoom plig. Raws li cov xaum tshuab siv tau ntev dua, nws tsis yog ib txwm muaj. Thaum cov hlau lead tsis yooj yim ntawm cov xaum siv tshuab tas li tawg thiab snaps, ces lawv yeej tsis kav ntev li ntev.
tus cwj mem tshuab siv hu ua dab tsi?
Thaum hu ua "mechanical mem hluav" hauv Tebchaws Meskas nws hu ua " xaum xaum" hauv UK thiab " cwj mem" hauv Is Nrias teb. Tus cwj mem no tsuas yog siv rau kev kos duab thiab kev sau ntawv, tab sis nws kuj tuaj yeem siv rau hauv kev kos duab zoo.