14. Is the strength of the nervous system increased by convulsions? This is so evident that it often requires four or five persons to confine a delicate woman to her bed in a convulsive fit. In like manner the strength of the arterial system is increased in a fever. This strength is great in proportion to the weakness of every other part of the body. 15. Do we observe certain nervous convulsions to affect some parts of the nervous system more than others, or, in other words, do we observe preternatural strength or excitement to exist in one part of the nervous system, while other parts of the same system exhibit marks of preternatural weakness or defect of excitement? We observe the same thing in the blood-vessels in a fever. The pulse at the wrist is often _tense_, while the force of the heart is very much diminished. A delirium often occurs in a fever from excess of excitement in the blood-vessels of the brain, while the pulse at the wrist exhibits every mark of preternatural weakness. 16. Is there a rigidity of the muscles in certain nervous diseases, as in catalepsy? Something like this solstice in convulsion occurs in that state of fever in which the pulse beats but sixty, or fewer strokes in a minute. 17. Do convulsions go off _gradually_ from the nervous system, as in tetanus, and chorea sancti viti? So they do from the arterial blood-vessels in certain states of fever. 18. Do convulsions go off _suddenly_ in any cases from the nervous system? The convulsion in the blood-vessels goes off in the same manner by a sweat, or by a hæmorrhage, frequently in the course of a night, and sometimes in a single hour. 19. Does palsy in some instances succeed to convulsions in the nervous system? Something like a palsy occurs in fevers of great inflammatory action in the arteries. They are often inactive in the wrists, and in other parts of the body, from the immense pressure of the remote cause of the fever upon them. From the facts and analogies which have been mentioned, I have been led to conclude that the common forms of fever are occasioned simply by irregular action, or convulsion in the blood-vessels. The history of the phenomena of fever, as delivered in the foregoing pages, resolves itself into a chain, consisting of the five following links. 1. Debility from action, or the abstraction of stimuli. When this debility is induced by action, it is sometimes preceded by elevated excitement in the blood-vessels, from the first impressions of stimuli upon them. 2. An increase of their excitability. 3. Stimulating powers applied to them. 4. Depression. And, 5. Irregular action or convulsion.