How do I know if HP88 printheads are empty? -

Ive got some HP88 Printheads but I dont know whether they are empty or unused, I dont have the printer to test them on so am wondering if there are any tell tale signs to know whether the printheads are used or new (weight, markings etc) Thank you for any help in advance!

take a white cloth and wipe the head in a straight line... if you get ink after 2 times of doing it then there is ink in them... i just tried it on the ones in my printer... also look at the injection end to see if you can see any color on them...