None deny that rigidity of the limbs can be effected mesmerically; but all mistake who impute the phenomenon to muscular ability, irritability, or energy. All flesh is _inert_; all muscular fibrine is flexible, bends from its own weight when held horizontally, and over it the will has neither power nor influence. Then, how is a muscle or nerve to stiffen itself, and where is the mechanical arrangement within for such purpose? The power is derived from without, and consists in medium of space. The de-electrising passes make entrance-room for influent medium of space, which is the cause of the limbs becoming rigid. As in Bramah's pump, water serves the purpose of an iron piston, so, within the nerves and muscles, medium of space in excess and under the general pressure, is an equally rigid piston, and the cause of all muscular strength and of rigidity. The depolarizing passes bring back electric matter, which displaces all excess of medium of space, and with it the physical cause of rigidity. PAIN. Pain is not removed but prevented by means of the passes. It is not excited in the mesmerised patient during severe surgical operations, because the movements of the brain, as is said of a watch with the finger on a wheel, are stopped. General insensibility being effected by pressure of the surgeon's finger on the brain of a fractured skull, so is it mesmerically effected by the nervous fluid, which has suffered increase as the nerves have been de-electrised by the passes. _Curative Mesmerism._--The curative principle of mesmerism seems to consist in correcting occasional irregularities in the _electric circulation_. By the passes, electric matter in excess is removed, which, from being noxious to the part, might contribute to the formation of mucus to become concrete, or otherwise injurious to the flesh: or, the passes may transfer the excess to supply deficiency elsewhere,--as in the case of gout, a disease of the sufferer's own making, from excess of de-electrising food and drink, which uncoats and unlines the nerves, and thus leaves the nervous fluid, from casual circumstances, to almost lacerate the brain. Stomach coating aliment, not denuding physic, is the cure: as electric matter may become a constituent of the humidities of the different organs, so may it of the serous fluid, which is indispensable to wholesome flesh. In all such cases mesmerism is curative.