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relation is intimate and important can scarcely be doubted. We require to determine that an especial characterise the nervous force, and distinguish it from all other forces with which we have to deal; and I would venture to suggest that chemistry promises something in this inquiry. Even in its general bearing, we observe very interesting material for reflection. I may here allude to the fact (mentioned on a former occasion within these walls), that the cerebro-spinal and sympathetic systems have their distribution so arranged that the cerebro-spinal branches terminate in acid fluid, whereas the sympathetic nerve is distributed over surfaces having an alka line reaction. I may add to this the striking fact, that the great sympathetic ganglia are strongly alkaline, while the brain and spinal marrow (and more especially the grey matter), if examined immediately after death, are scarcely neutral to test-paper, and become rapidly acid on exposure. I was enabled to establish these latter facts in the physiological laboratory of Guy’s Hospital, where the semilunar ganglia of a dog were dexterously obtained for me by my friend Dr. Pavy. I cannot but believe that great good would accrue, if those
