1 48 Trowbridge — In terJocking of Emargin ate 



2, 3. 4. 5 





Fig. 2. Primaries not interlocked, viewed from beneath the wing 



Fig. 3. Primaries interlocked, viewed from beneath the wing. 



Fig. 4. Primaries not interlocked, viewed from above the wing. 



Fig. 5. Primaries interlocked, viewed from above the wing. 



