My grandmother used to make coffee like this. The egg and eggshells were mixed with the coffee grounds before to coffee was boiled in a glass pot on the stove..the egg helped the coffee grounds stick together and stay at the bottom of the pot. It worked, but only partly. She still poured her coffee through cheesecloth in a small strainer to keep the rest of the grounds out of her cup.

As for the animal bones and egg shells. What would you say if I told you that I used cow manure in the production of my vegetables? Yup...it's fertilizer!
That may be what they were referring to as well. Bone meal and eggshell is sometimes used for fertilizer or as a soil enrichment.