Ink is generally made of pine or oil soot and animal glue, then dried in the wind or an oven. The end of inkstick has to be rubbed with a little water on the flat part of the inkstone. The Chinese grind in circles while the Japanese do it back and forth. From time to time, add drops of water, until the "pit" of the stone has a sufficient quantity of ink to start. It take some 10 to 15' but all masters say it is necessary to reach an ideal mental condition. NB Wipe inkstick when finished otherwise it would crack