"Four to five inches long; hides in the water among loose stones, feeds on the larvae of water-insects,…
"If the conducting wire is bent into the form shown, the lines of force will pas around the wire from…
"Thumb and leg and foot of Mystacina tuberculata." —The Encyclopedia Britannica, 1903
"Fleming's rule for direction of induced current. Extend the thumb, forefinger and middle finger of…