The custom of fumigating with odoriferous substances, does not therefore appear upon this view of the matter to be destitute of importance; indeed, the universal practice stamps it at once, as an efficacious remedy for the purposes of disinfection. The introduction of chlorine fumigation, seems to have superseded, in a great measure, the use of fragrant herbs and woods; and it is questionable whether the substitution be altogether desirable or

advantageous. Many scents may be agreeably and usefully employed, with much less chance of annoyance to the patient, and considerably less injury to articles of furniture, &c.

The fumigations of sulphurous acid and chlorine are, perhaps, more adapted as disinfectants in uninhabited apartments;—their power to destroy vegetation, is well known. They have been used, chiefly, with the idea of neutralizing gaseous exhalations, particularly chlorine, as it tends to combine with hydrogen, to form hydrochloric acid, and then to unite with ammoniacal matters, forming hydrochlorate of ammonia. This, supposing noxious or pestilential effluvia consisted of the ammoniacal exudations variously combined, was an exceedingly efficacious method of rendering them inert; but as we feel convinced that no ammoniacal compound could possibly be the cause of infection, we must look to the influence these gases possess over other forms of matter, and as they are so destructive, even in minute quantities, to vegetable existence, it is possible that their beneficial effects may be due to this property. The immediate neighbourhood of gas works is prejudicial to vegetation, I imagine, from the amount of sulphurous vapours, and to this has been attributed the exemption of persons employed in these works. Many other instances might be cited of a similar nature.

I have now to speak of medicinal agents, and here comes a considerable difficulty.

If we might believe all that has been written on the sure and certain remedies for the "ills that man is heir to," we should be led to acknowledge that both nature and art were prodigal in antidotes and specifics. The all-bountiful hand of nature, I do not doubt, has at the same time scattered the seeds of good and of evil. The fertilizing showers fall to irrigate the soil, and produce food and nourishment to man; here and there is the reeking morass "feeding unnatural vegetation," and if man takes up his abode in its vicinity, the rains which made it unhealthy, have also made it highly fertile; by labour and cultivation he may convert the mephitic bog into a waving corn-field, and the seeds of life and sustenance be made to supplant the seeds of death and corruption.

It is generally believed, that where there are particular and specific diseases, there also may be found appropriate and specific remedies; the discoveries of chemistry, it is not improbable, may in some respects have retarded the progress of natural medicine. In the early ages of the world, the "healing plant" must have formed the staple of medical commerce, for though Tubal Cain[[73]] has been considered as the first surgical instrument maker, because he was the first artificer in brass and iron, we have not discovered that chemical compounds entered into the composition of physic, till very

many years after his time. To the alchemists we owe the science of chemistry, and much of the physic of the present day may be traced to them. The multiplicity of ingredients which at one time entered into the composition of one dose of physic could only be spoken of under the title of "legion." Who shall specify the active and curative ingredient (if there be one), when from five to a hundred may have been exhibited at the same time? It has been the pride of our physicians, that the pharmacopœia has been simplified; it has not reached its most simple form yet. That many simple plants have specific and wonderful power over disease, is an indubitable fact, but I firmly believe that the laudable, though mistaken efforts of physicians to improve their effect by various combinations, have been the means of throwing many valuable medicines into oblivion; I must also add, that cheap physic and adulterations have had no small share too in the banishment of much valuable physic from ordinary practice. It has been believed, and I think with much reason, that a thorough search into the qualities of plants, would shew that "they are capable of affording not only great relief, but also effectual and specific remedies." "That they are not already found, is rather an argument that we have not been sufficiently inquisitive, than that there are no such plants endued with these virtues."

Of the result obtained by medical treatment, in cases of epidemic or infectious disease, it is most

difficult to speak, but as my province here is only to shew that living germs are the morbific agents, I have but to refer to such remedies as have been most extolled in controlling these affections. The disinfectants have already been mentioned in a cursory manner. An enumeration only of simple medicines used during the late Epidemic, shall conclude this work, as the treatment in former times could not by any possibility furnish satisfactory information. Aromatics and fragrant stimulants have in all times taken the foremost rank with acids, such as vinegar, lime and lemon juice. Mr. Guthrie's adoption of lemon juice in preference to bark, which he said made him worse while suffering from an attack of fever, during the Peninsular campaign, and his speedy recovery from the disease, though not from its effects, shews, when many others can bear equal testimony to its value, that such a remedy though simple is not to be despised.