That is a Palmer's Hot Pot it works well for pure lead, and making BP bullets that are of pure, or darn near pure lead. It works for making fishing sinkers, and jig heads. For most bullet alloys it is not that great to work with. It can be used, though there are other electric melting pots that will work better for close to the price of that one.
A thermometer has been mentioned. Once I started using one my rejects per session decreased greatly.
No matter how many times you do it and nothing happens it only takes something going wrong one time to kill you.