this is a grenade found at https://www.google.com/url?sa=i&url=http%3A%2F%2Fwww.deactivated-guns.co.uk%2Fmilitaria%2Finert-wwi-no5-mills-bomb%2Fgrenade%2Fprod_2020.html&psig=AOvVaw3UAHWmEyAVNFQwlWyzlRXc&ust=1580240886427000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCOj5m6vGpOcCFQAAAAAdAAAAABAJ unlike the bombs that where droped by planes, these where thrown by hand.
this is a German bomb used in WWI found at https://www.google.com/url?sa=i&url=http%3A%2F%2Fwww.deactivated-guns.co.uk%2Fmilitaria%2Frare-inert-ww1-german-granatenwerfer-mortar-bomb%2Fprod_6128.html&psig=AOvVaw3UAHWmEyAVNFQwlWyzlRXc&ust=1580240886427000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCOj5m6vGpOcCFQAAAAAdAAAAABAD bombs like this one where dropped by planes and played a big role in the war