By June of 1875, Bell had constructed a &quot;harp apparatus,&quot; which created an electrical current using sound waves and a long magnet.
(Bell; had constructed; a &quot;harp apparatus,&quot; which created; T:By June of 1875) (a &quot;harp apparatus,&quot; created; )
Bell a &quot;harp apparatus,&quot
had constructed created
a &quot;harp apparatus,&quot which created T:By June of 1875