That face when the opposum was licked tho 😖

Some people call before 2000 as 1900s.

Thank you for the explanation. Hopefully I learn something from the reference you linked. I’ll watch the video first before reading the literatures.

Thank you for taking the time to explain the topic to me. I appreciate it. I’ll try to read the book.

What does “material analysis” means in this context? What should I search to know more? I searched the term and only came up with chemistry topics.