3837. It was perceived that such represent the isthmus in the brain which is situated between the cerebrum and the cerebellum, from which and through which the fibers are diffused, and whithersoever they extend, they act diversely in the extremes, but yet in their [first] principle they act in the same or a similar way; and also that they represent the ganglia into which a [single] nerve flows, and out of which issues a multitude that part asunder and spread, some this way and some that, and which act indeed dissimilarly in their ultimates, but because issuing from one ganglion, they act from one principle, and thus while in ultimates they act dissimilarly according to appearance, yet in themselves they act alike as to end, which is one; and so in many other things. - 1748, November 2, 3.