Protons are so small that a little dib of ink like the dot on this i can hold something in the region of 500 billion of them, rather more than the number of seconds contained in half a million years.

像字母i上点这样一滴墨水，就可拥有约莫5000亿个，得更确切一点，要比组成1.5万年秒数还多。