The power and the weight may thus be said to reciprocate, the two sitting as it were side by side and blending their peculiar influences to produce a common result, as indicated at fig.
These surfaces may be conferred on artificial wings, aeroplanes, aerial screws or similar structures; and these structures, if we may judge from what we find in nature, should be of moderate size and elastic. The power of the flying organs will be increased if they are driven at a comparatively high speed, and particularly if they are made to reverse and reciprocate, as in this case they will practically create the currents upon which they are destined to rise and advance.
He is said to have been parsimonious, and certainly he was quicker to receive than to reciprocate hospitalities; but his mean establishment and mode of life are explained by the retired habits of his wife, and her dislike of company.
The term of office of the latter was marked by the first tentative efforts to modify the high protective system by which British trade was hampered, especially by the Reciprocity of Duties Act (1823), a modification of the Navigation Acts, by which British and foreign shipping were placed on an equal footing, while the right to impose restrictive duties on ships of powers refusing to reciprocate was retained.