Sonic precautions are proper in conducting the vaccine inoculation. The choice of matter should be carefully at tended to. It should be taken from a good vaccine vesicle, in a healthy subject, from the 5th to the 9th day of the dis ease. It is most certain in its effects when immediately inserted. If it is to be kept, it should be allowed to dry. Some confine it, in order to preserve it in its original moist state. They are not aware that it is subjected to much greater change by moisture than by exposure to the atmo sphere. It may be kept on glass, or on the point of a lan cet, or on the end of a small pointed piece of ivory. Mr. Bryce has suggested the employment of the crust, which, in its central part, contains matter dried in an early stage of the disease, and therefore perfectly pure and safe, and from which the light coloured part round the margin ought to be removed. Dried matter, in these different forms, is con venient for transportation ; when about to be used, it most be moistened with water, either cold, or of a blood heat ; but recent matter is always preferable, and therefore ought to be secured in every populous place, by regular weekly inoculations.
The end of the third month, NvIvvi the constitution has acquired some firmness, and before it is subjected to the disadvantages of the period of teething, is the most eligible time for the operation. In an adult in whom it has been neglected, it should be performed when the constitution is in its soundest state ; when, for example, no cutaneous dis ease is present, and in females when there is no pregnancy, and when the catamenia are absent. But, when the conta gion of small-pox prevails in a neighbourhood, these disad vantages must he disregarded.
With respect to the mode of insertion, the object kept in view is, to secure the contact of the matter with the cu bs vcra. The operator, therefore, should delicately raise the cuticle, without any effusion of blood if possible, and apply the matter to the abraded part. The method of do ing this, which Mr. Bryce has found most certain of suc cess, is, first to lay a drop of the matter on the sot face, and then make several lighht punctures through this matter and the cuticle with the lancet. It is then to be held exposed to the air, but not to an artificial fire, till it dries, and after wards left to itself.
The inoculator must now mark its course, whether it is conformable to that which we have briefly stated, which is described by authors, and delineated in their plates. These last, however, afford but feeble assistance, unless the ope rator has already seen the disease as it appears in nature. The spurious cow-pox is semetimes accompanied with a severe phagedenic ulcer, instead of a regular vesicle. It would be proper to watch the constitutional synintoms, viz. the heat of the skin, and the state of the pulse. It is better, however, to use the test invented by Mr. Bryce. If irre
gular eruptions appear during the progress, or after the termination of the vaccine affection, we ought to guard against cold, which might suddenly repel them. and gene rate a visceral affection. If daily cold ablutions have been hitherto used, these should be intermitted in such cases, and tepid bathing substituted. It is always necessary to protect ehc vesicle from being rubbed and broken, as such an accident destroys its efficacy. When it happens to be broken, Mr. Bryce directs that the further discharge of its contents should he prevented, and the regular course of the alicction restored, by cold applications and chemical astrin gents. If a troublesome sore is formed at a late stage of the affection, astringents and escharotics ought to be em ployed, on surgical principles similar to those adopted for other ulcers presenting a similar appearance. NVIren the vesicle is formed, but the inflamed areola is too late in ap pearing, the part should be exposed to the heat of a fire, in order to quicken the local action, on which the regular phenomena depend. Where the local inflammation is ex cessive, or where a tumour is formed in the axilla, laxatives should be used, accompanied with cooling applications, or with fomentationy, according to the state of the parts. If febrile symptoms should in any case be immoderate in de gree, they arc to be alleviated by the usual antiphlogistic treatment.
The success of the practice of variolous inoculation led the late Professor Home of Edinburgh to make some ex periments for the inoculation of measles, which gave en couragement to other attempts of the same kind. But the disease was not found to be easily communicated in this manner. The operation was performed by means of the blood of a patient under the disease.
Repeated daring trials have even been made to inocu late the plague. These, for the most part, have either terminated in the death of the person who made himself the subject of the experiment, or have failed to cornmu ideate the disease. See WOodville's History of the Ino culation of Small-Pox in Great Britain. Jenncr's Ob servations on the Cow-Pox ; his Further Observations ; and his Continuation of Facts and Observations. Pcarson's Inquiry. \Voodville's Reports of Inoculation for Cow Pox ; and his Observations on Cow-Pox. The Writ ings of Moseley, Rowley, and Birch, (in opposition). Brown on Cow-Pox. works of Willan, Moor, Ring, Lettsom, and Thornton. The Compends by Aiken, Bell, and others. Bryce's Practical Observations on the Inocu lation of Cow-Pox. Sanders' Comprehensive View of Small-Pox, Cow-Pox, and Chicken-Pox. Dcwar's ?c count of an Epidemic Small-Pox in Cuper. The Medical and Physical Journal; Duncan's ?nnals of Medicine ; The Edinburgh Medical and Surgical Journal, and other medi cal periodical works passim. (H. I).)