C. A, Morey—Phonautograph. 131 
lever. This may be of any length (the one used was about 
twelve inches) and is made very slender and light, either of deal 
or of a stiff straw. This is attached at the end to the brass ring 
which holds the membrane by a simple hinge of goldbeater’s 
skin, and also to the membrane itself by a short, flexible 
bristle, or piece of broom-corn. This is inserted into the lever, 
and is fixed with a drop of glue; the other end is fixed to the 
membrane as the style usually is, either by a drop of glue, or 
sealing wax, the former being preferable. Now it is evident 
that the former longitudinal motion of the style will impart a 
lateral motion to the lever, and thus to the ityle at the free end 
of it; and also that this motion will be greatly magnified. 
The curve can now be drawn upon a plate of smoked glass, as 
in the well known experiments with tuning forks, the plate be- 
ing drawn under the style in the direction of the length of the 
lever. The whole attachment can readily be made so light as 
to encumber the membrane but very little. 
The following curves will serve to show the advantage 
gained over the usual attachment, as well as to suggest the 
1 Wyrm ri 
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numerous uses to which the instrument can be put. The first 
one is the toungue trill, or the German r prolonged; the sec- 
is the 00 in mood. The fact that a difference in the intensity of 
the sound shows itself so very plainly in the curves (2), seems 
to suggest something in the way of quantitative work in that 
direction, but it is yet a question as to the delicacy of the instru- 
ent 
In each of the cases above, the sound was made in front of 
the parabolic condenser, but at some little distance from it— 
two or three feet. 
‘Mass. Inst. Technology, Boston, May 24, 1874 
