On the Electromotive Properties of the Leaf of Dionaea in the Excited and Unexcited StatesSecond Paper . ed with solid paraffin. Around this a similartrough of the same material, b, also filled with paraffin, revolves, so that it can beplaced in any desired position with reference to a; c, is another trough of the sameconstruction as b; a short trough* d, which travels in an annular groove, so that itcan be placed in any required relation to c, contains the pool o ; o, o and e, e areseverally connected with binding screws correspondingly marked out but not shownin the diagram, of which o, o ar
On the Electromotive Properties of the Leaf of Dionaea in the Excited and Unexcited StatesSecond Paper . ed with solid paraffin. Around this a similartrough of the same material, b, also filled with paraffin, revolves, so that it can beplaced in any desired position with reference to a; c, is another trough of the sameconstruction as b; a short trough* d, which travels in an annular groove, so that itcan be placed in any required relation to c, contains the pool o ; o, o and e, e areseverally connected with binding screws correspondingly marked out but not shownin the diagram, of which o, o are in the battery circuit, and €, e in the circuit of thegalvanometer. It wxill be readily seen that when the bar revolves in the directionof the arrow, o, o will be first closed, then e, e ; but, inasmuch as the battery andgalvanometer circuits are never closed at the same time, and both include the electrodeswhich are applied to the opposite sides of the leaf, the battery current is led into theleaf during the parts of the revolution limited by the radial dotted lines w, a>\ and the Diagram 18= ,^y„!i~«*—g-gp. ) r leaf difference led off through the galvanometer during the part limited by thelines 7], 7]\ Before each experiment the instrument is adjusted, and the duration ofthe contacts, as well as the interval between them, is measured by connecting bothcontacts with a Desprezs time-marker, which inscribes them on a smoked surface. The purpose of this arrangement is to determine not only the immediate effectproduced on the leaf by leading through a battery current for a very short period, butalso to ascertain the duration and time relations of the effect by measurements madeat periods following each other at regular intervals. The method of observation is asfollows :— The revolving bar of the rheotome is placed in such a position that the galvanometercircuit is permanently closed. The difference of potential between the upper am 422 PROFESSOR J. B. SANDERSON O
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Keywords: ., bookcentury1800, bookdecade1880, bookidphiltrans019, bookyear1888
