THE FIRST TELEPHONE. 
49 
nexion respectively with the support of the pivotted lever and 
with the vertical spring. A springy strip of platinum pressed 
against the end of the pivot of the lever (as shewn enlarged in 
fig. 5) to ensure good electrical contact. 
If now any words, or sounds of any kind, were uttered in 
front of the ear,” the membrane was thereby set into vibrations 
as in the human ear. The little curved lever took up these 
motions precisely as does the “ hammer ’’-bone of the human 
ear ; and, like the “ hammer ’’-bone, transferred them to that 
with which it was in contact. The result was that the contact 
between the upper end of the lever and the spring was caused to 
vary. With every rarefaction of the air the membrane moved 
forward, and the upper end of the little lever moved backward, 
and pressed more firmly than before against the spring, making 
better contact, and allowing a stronger current to flow. At 
every condensation of the air the membrane moved backwards 
and the upper end of the lever moved forward, so as to press 
E 
