 
 <prompt> Wetin Bell talk say need to happen make the metal detector work? Given the previous question, write a context wey contain the answer. E fit be 1 - 20 sentences. Context: <response>: Bell na im dem give credit for developing one of di early versions of metal detector for 1881. Di device bin quickly put together to find di bullet wey dey inside di body of U.S. President James Garfield. According to some accounts, di metal detector work well for tests but e no fit find di assassin bullet because di metal bed frame wey di President dey lie on disturb di instrument, wey cause static. Di president surgeons, wey dey doubt di device, ignore Bell request to move di president go another bed wey no get metal springs. Alternatively, even though Bell don detect small sound for im first test, di bullet fit dey too deep for di crude apparatus to detect. 