\£ E Hopkins on. 
Sheet II. 
Correct SynthesLs of ch&rcuUerisdo curve. 
A. Armature E. Obscr-vatcorus, + ascendx/tfj, © descericbirig,. 
Phil. Trans. 1886 . Plata 17 . 
B Air space' 
G Yoke?. 
jjine- {nte^ral of McugrvUi^\ 
West, Newman Sc Co htVi 
