How to make turtle specimens

In Shang Dynasty, tortoise shell was used for divination to know the meaning of ghosts and gods. The method of making tortoise shell specimens can be referred to as follows.

After turtle shell (or cattle scapula) is taken, it is soaked in salt water first, and then dehydrated and degreased with alkaline earth. Repeat this many times, put it in a shady and ventilated place, and finally punch holes for divination.

In divination, the prepared log should be burned to a red Mars (there can be no fire), and then the log should be tightly inserted into the hole to rotate, because the tortoise shell is extremely dry and the hole is thin, and cracks will appear at high temperature, and then the meaning of mountains, rivers and ghosts can be interpreted according to the signs appearing above.