Among these the smallpox, so dreaded on account of the great number of its serious symptoms, occupies a prominent position, and it has removed and cured a number of maladies with similar symptoms.

How frequently does smallpox produce violent ophthalmia, sometimes even causing blindness! And see! by its inoculation Dezoteux cured a chronic ophthalmia permanently, and Leroy another.

An amaurosis of two years' duration, consequent on suppressed scald-head, was perfectly cured by it, according to Klein.

How often does smallpox cause deafness and dyspnoea! And both these chronic diseases it removed on reaching its acme, as J.Fr.Closs observed.

Swelling of the testicle, even of a very severe character, is a frequent symptom of smallpox, and on this account it was enabled, as Klein observed, to cure, by virtue of similarity, a large hard swelling of the left testicle, consequent on a bruise. And another observer saw a similar swelling of the testicle cured by it.

Among the troublesome symptoms of smallpox is a dysenteric state of the bowels; and it subdued as Fr. Wendt observed, a case of dysentery, as a similar morbific agent.

Smallpox coming on after vaccination, as well on account of its greater strength as its great similarity, at once removes entirely the cow-pox homoeopathically, and does not permit it to come to maturity; but , on the other hand, the cow-pox when near maturity does, on account of its great similarity, homoeopathically diminish very much the supervening smallpox and make it much milder, as Muhry and many others testify.

The inoculated cow-pox, whose lymph, besides the protective matter, contains the contagion of a general cutaneous eruption of another nature, consisting of usually small, dry (rarely large, pustular) pimples, resting on a small red areola, frequently conjoined with round red cutaneous spots and often accompanied by the most violent itching, which rash appears in not a few children several days before, more frequently, however, after the red areola of the cow-pock, and goes off in a few days, leaving behind small, red, hard spots on the skin;-- the inoculated cow-pox, I say, after it has taken cures perfectly and permanently, in a homoeopathic manner, by the similarity of this accessory miasm, analogous cutaneous eruptions of children, often of very long standing and of a very troublesome character, as a number of observers assert.

The cow-pox, a peculiar symptom of which is to cause tumefaction of the arm, cured, after it broke out, a swollen half paralyzed arm.

The fever accompanying cow-pox, which occurs at the time of the production of the red areola, cured homoeopathically intermittent fever in two individuals, as the younger Hardege reports, confirming what J. Hunter had already observed, that two fevers (similar diseases) cannot co-exist in the same body.

The measles bears a strong resemblance in the character of its fever and cough to the whooping-cough, and hence it was that Bosquillon noticed, in an epidemic where both these affections prevailed, that many children who then took measles remained free from whooping-cough. They would all have been protected from, and rendered incapable of being infected by, the whooping-cough in that and all subsequent epidemics, by the measles, if the whooping-cough were not a disease that has only a partial similarity to the measles, that is to say, if it had also a cutaneous eruption similar to what the latter possesses. As it is, however, the measles can but preserve a large number from whooping-cough, and that only in the epidemic prevailing at the time.