The Plague at Marseilles Consider'd

The Blights which are attended with large Worms or Caterpillars, seem to be rather hatch’d with the East Wind, than that the Eggs of those Creatures are brought along with it; but those Blights which produce only those small Insects which occasion the curling of the Leaves of Trees, may proceed from Swarms of them, either hatch’d or in the Egg, which are brought with the Wind.

Some perhaps may object, that the East Wind is too cold to hatch these Creatures; how comes it then that we find them hatch’d when those Winds reign? Or is it reasonable to conjecture that the same degree of Heat is necessary to enliven an Insect as is required to hatch the Egg of a Pullet? The Insects of Norway, Iceland, and such like cold Climes, must certainly have less Heat to produce them, than Creatures of the same Race must necessarily have in those Climates which lye nearer to the Sun. Every Creature, without doubt, requires a different Period of Heat or Cold to enliven it, and put it in Motion, which is prov’d by so many known Instances, that I conceive there is no room for any dispute upon that score.

But there may yet be another Question, viz. Whether it is not the East Wind of it self that blights, without the help of Insects? But that may be easily resolved on my side; for that if it was the Wind alone that blighted, then every Plant in its way must unavoidably be infected with its Poison; whereas we find the contrary on a single Branch it may be, or some other distinct Part of Plants.

And again, to shew how reasonably we may conjecture that ’tis Insects which thus infect the Trees, let us only consider, that every Insect has its proper Plant, or Tribe of Plants, which it naturally requires for its Nourishment, and will feed upon no other kind whatsoever: Therefore ’tis no wonder to see one particular sort of Tree blighted, when all others escape; as for Example, that Wind which brings or hatches the Caterpillars upon the Apple-Trees, will not any way infect the Pear, Plumb, or Cherry with Blights, because, were the Shoals of Insects natural to the Apple, to light only upon those other Trees mentioned, they would then want their proper Matrix to hatch in; or if they were hatch’d already, they would Perish for want of their natural Food; so that ’tis morally impossible that all sorts of Trees should be blighted at the same time, unless the Eggs of every kind of Insect, natural to each Tree, could be brought at one time with the Wind, or that an Easterly Wind could contain in it at once, as many differing Periods of Cold or Heat, as would be requir’d to hatch and maintain each differing kind of those Creatures.

The common People in the Country seem to be of my Opinion, that Blights are brought by the East Winds, which they are so well satisfied brings or hatches the Caterpillar, that to prevent the too great Progress of Blights, it is common for them when the East Winds blow, to provide large Heaps of Weeds, Chaff, and other combustible Matter on the Windside of their Orchards, and set them on Fire, that the Smoak may poison either the Insects or their Eggs, as they are pass’d along. By this Contrivance I have often known large Orchards preserv’d, when the neighbouring Parts have suffer’d to the Loss of all their Fruit.

And I have also seen these Fires made with good Success to destroy the Caterpillars, even after they were hatch’d, and had began to devour the Trees, by suffocating them, and forcing them to drop to the Ground, where they have been swept up in large Quantities, and kill’d. I have heard it affirm’d by a Gentleman of Reputation, that Pepper-Dust, being powder’d upon the Blossoms of any Tree, will preserve them from Blights, which may be, because Pepper is said to be present Death to every Creature but to Mankind. Now altho’ this last Secret is too costly for common Use, yet it may be of Service in some particular Place for the Tryal of a new Tree, where a Taste of the Fruit is desired, and besides it helps to inform us, that Blights are occasion’d by Insects, or their Eggs, lodging upon a Plant, and that Pepper Dust will not suffer them either to live, or to be hatch’d.

Another Remark (which to me is Demonstration) that Blights proceed from Insects, or their Eggs (being brought with the Easterly Winds) was the total Destruction of the Turneps, Ann. 1716, on the West Side of London; about October we had dry Easterly Winds for a Week or ten Days, and several thousand Acres of Turneps, which were then well grown, turn’d Yellow and decay’d, unless in such Places only as were shelter’d by Hedges, Houses, or Trees, where they remain’d Green ’till the Insects, which came with the Wind, in about a Week’s Time, destroy’d those also. Some Farmers imagin’d that the Birds which were there in great Flocks, had eaten the Leaves of their Turneps, and contriv’d all Means possible to destroy them, ’till I convinc’d them that the Birds were rather Friends than Enemies and came there to feed upon the Caterpillars, which were in such great Numbers, that each Turnep-plant had not less than a Thousand upon it; and that Insects frequently pass in Clouds and numberless Armies after this manner, is plain from several Instances, which have happen’d in my Time, and one of them (I think in June, Ann. 1717) passing over London were suffocated (I suppose) with the Smoak of the Sea-Coal, and drop’d down in the Streets, insomuch that a square Court belonging to the Royal Society was almost cover’d with them; these were of the Fly Kind, and fully perfected.

It may be asked, perhaps, how these Insects came to destroy the Turneps only, and not touch the other Greens of the Fields, as Cabbages, Carrots, Parsnips, and the like? Every Herb has its peculiar Insect, like the Trees I have mention’d: Nay more than this, the Insects which Nature hath design’d to prey upon the Flower of a Plant, will not eat the Leaves, or any other Part of the same Plant. The Leaves of Plants have their Insects natural to them, the Bark and Wood likewise have their respective Devourers; and those several Insects have other Kinds, which lay their Eggs, and feed upon them.

I could yet give a much larger Account of Animals and Plants, how they have been particularly Infected, but I rather choose to refer my Reader to the Chapter at large, of Blights and Plagues, in my New Improvements of Planting and Gardening, &c.

By the foregoing Accounts we may observe, that Mankind, Quadrupedes and Plants seem to be infected in the same manner, by unwholesome Insects; only allowing this Difference, that the same Insect which is poisonous to Man, is not so to other Animals or Plants, and so on the contrary; we observe likewise, that Pepper which is of Use to Mankind, is poisonous to other Creatures, and tho’ a Man cannot eat of the Cicuta, or Hemlock, without prejudice, yet a Cow and some other Animals will eat it to their Advantage; and the Manchanese Apple, which is deadly Poison to almost every Creature, is eaten greedily by Goats, and which is strange, the Milk of those Goats is wholesome to Mankind. Again, we may remark that Camphire which may be taken at the Mouth by the Human Race, and is helpful in many Cases, will destroy Insects; for among the Curious who have Cabinets of Rarities, it is a common Practice to lay it in their Drawers and Cases, to destroy the smaller kind of Insects, which would otherwise devour their Collections.

The Smoaking of Tobacco is helpful to some Constitutions, but was the pure Leaf to be taken directly into the Stomach, it would Purge in a violent Manner, and the Oil of it as I am told is a deadly Poison; however it is to be remarked, that in the time of the last Plague in London, Anno 1665, that Distemper did not reach those who smoak’d Tobacco every Day, but particularly it was judged the best to smoak in a Morning. We have an Account of a famous Physician, who in the Pestilential time took every Morning a Cordial to guard his Stomach, and after that a Pipe or two before he went to visit his Patients; at the same time we are told, he had an Issue in his Arm, by which, when it begun to smart, he knew he had received some Infection, (as he says) and then had recourse to his Cordial and his Pipe, by this means only he preserved himself, as several others did at that time by the same Method. I suppose therefore, that the Smoak of Tobacco is noxious to these Venomous Insects, which I believe to be the Cause of the Plague, either by mixing it self with the Air and there destroying them, or else by provoking the Stomach to discharge it self of those Morbid Juices which would nourish and encourage them.

When I consider that the dead Bodies of the miserable People of Marseilles were found full of Insects, and that those Worms could be no way so suddenly killed, as by putting Oil or Lemon Juice upon them, it brings to my Mind several Tryals I have made upon Insects of various Kinds, in order to occasion their speedy Death. In these Experiments, I found that most of the larger Kinds would live some Minutes in Spirit of Wine and other spirituous Liquors, when they were forced into them, and that Oil immediately suffocated them, from whence I suppose, the Air, or Breath they draw, is exceeding fine and subtile, and that a thick Air consists of too gross Parts for them to breath, and that since Oil destroys the larger Kinds of them immediately, the Oleagenous Particles evaporating from such Bodies as Oil, Pitch, Tar, &c. expanding themselves, and mixing with the common Air, would render it too thick for the smaller Kinds to subsist in.

We observe likewise that all Aromatick Herbs, &c. were found useful in the time of the dreadful Pestilence in 1665, which helps to confirm what I have just now related, for a single Leaf of Rosemary contains at least 500 little Bladders of Oily Juice, which by rubbing, break and afford that grateful Smell we find in that Plant, but in that as in all other Aromatick Herbs, was we to bruise the Leaves ’till all those Bladders were broken, the recreating Smell would be lost, and we should find only remaining an earthy, disagreeable Flavour, arising from the common undigested Sap; so if we take the Leaves of Fifty several Kinds of Aromatick Plants, and after bruising them, make up distinctly the bruis’d Leaves of each into Balls, and dry them by the Sun, or otherwise, they will all afford the same Smell; for the breaking of those Bladders, or Blisters, which yield the different Smells (from the Essence they severally contain) makes them lose all their Spirit or Essence.

In the Culture of these Aromatick Herbs, such as Rosemary, Lavender, Thyme, &c. we may remark, that they are never destroy’d by any Insect, which may still give us a further Proof of the Antipathy all Insects have to them, for which Reason some People are used to smoak their Houses with these Aromatick Herbs, but especially where the Chambers or Rooms are small and close; and it has been proved, that the Burning of Aromatick Gums and Woods, have likewise been useful in purifying the Air in a House, and preventing the Spreading of Pestilential Distempers.

In 1665 it was observable, that in Aldermanbury, and other Places, where there were large Ware-Houses of Aromatick Druggs, the Infection did not reach; so that it seems where there is Quantity enough of such Woods or Gums, as yield a strong Smell, we have no Occasion of burning them, the bare Effluvia rising from a large Mass, having the same Effect as burning a small Quantity. As every one of these Druggs, or Gums, is more pungent or operative upon the Organs of Smelling, so we may be assured, the Vapour proceeding from them fill a larger Space in the Air; but perhaps a Tun Weight of the strongest Aromatick among them, in the Body or Mass, will not purifie so much Air as half an Ounce of the same will do by burning; for the Smoak of a few Grains of Tobacco, when the Air is clear, will sensibly touch the Smell above forty Yards, tho’ a Pound of the Herb unburnt will not affect the Smell above a Foot.

These Observations may serve to inform us, that the burning of Aromaticks may help to keep the Air in an healthful State; but as Men of Business must often change their Station, and pass thro’ different Degrees and Tempers of Air, it is for that Reason, that Aromaticks, and strong smelling Roots, Herbs, &c. are recommended to be taken into the Stomach. The Cordial which we call Plague-water, compos’d of Aromatick Herbs, has been used with Success, as has also been Conserves of Rhue, &c. and the Use of Garlick in the Amiens Distemper, particularly, is remarkable. To this I may likewise add a Relation I had lately from some Men of Quality concerning a Plague, which some Years since destroy’d a great part of the French Army: It was observable, that at that time the Irish Regiments in that Service were preserv’d by rubbing their Bread every Morning with Garlick, which undoubtedly must taint their Breath for many Hours, and so regulate the Air about them, that the unwholesome Insects could not approach them.

Upon this Occasion, I cannot omit observing the extraordinary Remedy for destroying the Insect call’d the Wevil in Corn or Malt, as it was communicated to me by the Learned Dr. Bentley, Master of Trinity College, Cambridge; that worthy Gentleman tells me, that the Herb Parietaria, or Peletory of the Wall, is a Sovereign Remedy against the Wevil in Corn or Malt; and according to the Information he has had, an Handful of that Plant being laid here and there in a Granary infected by those Insects, will infallibly destroy them in a Day or two; which Discovery is so useful, that I think it ought to be made as publick as possible, and in this place serves to confirm my Hypothesis, That the Effluvia of some Plants are Destructive to Insects.

In the next place I come to consider, how much a certain Quantity of Air is requisite to preserve a single Animal Body, and the Knowledge of that, is what I account one of the chief Preservatives of Health. I have often been concern’d to find a Family of six or seven pinn’d up in a Room, that has not contain’d Air enough for the Maintenance of Health in one single Person; but such is the Hardship of our Poor in many Places, and is frequently the Occasion of their Death.

We may easily conceive how this happens, if we examine the Case of the Diving Tub, how short a while a Man can live it, without a Supply of fresh Air; the occasion of which is, that when he has drawn in with his Breath, all the Grosser Parts from the Air enclos’d in the Tub, the rest grows hot and suffocating, by being too much rarified.

From whence I suppose, a Room of Nine or Ten Foot Cube, will contain Air enough to keep a single Man alive for one Day, but if two were to inhabit that Space for the same time, each would receive but half his Nourishment, and so both would be Sufferers; but a Room, perhaps, containing twice that Space, might well enough serve five People for a Day, supposing that all External Air was kept from Communication with such a Room, during the time the People were in it; for, as I have observ’d, that Air has certain Nourishing Qualities in it, for the Maintenance of Human Life; so when those Nourishing Parts are imbibed, and drawn in by the Lungs, the Air is return’d and flung out as invalid, and cannot be of Use a second Time to the same Person; an Example of which, we find very curiously demonstrated by Mr. Newyentyte; he tells us, that in making this Experiment, he discover’d that the same Nourishing Quality in the Air, which is necessary to maintain Human Life, is also necessary to maintain Flame, which he proves thus:

A lighted Candle being set under a Bell, closely fix’d upon a Table, will burn perhaps a Minute or two in Proportion to the Quantity of Air pent up with the Candle in the Bell; but as soon as the Quality in that Air, which is necessary to feed the Flame, is exhausted, the Candle goes out; this has been often try’d with the same Success; and we find, that by letting into the Bell some fresh Air, a little before the Candle should have gone out, it will still continue burning: And then to shew that this Quality in the Air is the same which feeds the Life in Humane Bodies, it was try’d, whether the Air, returning from the Lungs, would not have the same Effect upon the Candle, as the External Air had before, but it had not, the Candle went out at its usual Time: Thus, it seems, when we suck in Air for Breath, the Lungs takes what is necessary for the Nourishment of our Bodies, and returns back the rest.

After this we may naturally conclude, that where the Rooms, or Houses are small, there ought to be frequent Admissions of the External Air, but especially where those Rooms or Houses are too much crouded with People; and if it is supposed that the External Air is Infectious, the burning of Aromaticks, Gums, or Herbs, upon the letting in of fresh Air, is necessary.

From the foregoing Observations we may learn, that all Pestilential Distempers, whether in Animals or Plants, are occasion’d by poisonous Insects convey’d from Place to Place by the Air, and that by uncleanly Living and poor Diet, Humane and other Bodies are disposed to receive such Insects into the Stomach and most noble Parts; while, on the other Hand, such Bodies as are in full Strength, and are well guarded with Aromaticks, would resist and drive them away, but chiefly how necessary it is to allow the Body a Freedom of Air, and how to correct it if it is Infected.

And I shall conclude with some Memorandums taken from the Papers of a learned Gentleman, who in the time of the late Plague in London was curious enough to make his Remarks upon the Signs of that Distemper, and the Method of its Cure.

He tells, the Plague proceeds first from a corrupted and unwholsome Air.

The Second, is putrified Humours, hot Blood, caused by breathing in such corrupt Air; and if the Diet before were perverse, it fills the Body with superfluous Humours.

Concerning the common Fear of Infection, which makes many rich Men, which might and ought to maintain poor visited People; and some Physicians likewise, whose Duty it is to administer Physick to them, flee away, so that in time of great Infection we hear more cry out for want of Bread and necessary means, than for anguish of the Disease.

Hence also came that inhumane Custom of shutting up of Houses that are visited with Pestilence, dejecting their Spirits, and consequently making way for the Disease, and taking Men from their Labour, which is a digester of Humours, and a preserver of Health; and if the Disease be Infectious (as in their Opinion it is) it is plain Murder, to shut Men up in an infected and destroying Air.

But all Mens Bodies are not full of Humours; if they were, all would be infected.

After this I find the following Directions to prevent Infection. First, To avoid the Fear of it, and support the Spirits in the next place. Secondly, To keep the Body soluble, and to use the juice of Lemons often. Thirdly, he recommends a Diet of quick Digestion, and to eat and drink moderately: He prescribes likewise the Smell of Aromaticks, such as Camphire, Styrax, Calamites, Wood of Aloes, &c. and to be taken inwardly, Mithridate, Anjelica, and Petasetis-Roots; and, in an express Manner, he recommends Cleanliness, and the Choice of a clear Air.

After Infection he tells us the Signs are an extraordinary inward Heat, a Difficulty of Breathing, a Pain and Heaviness in the Head, an Inclination to Sleep, frequent Vomiting, immoderate Thirst, a Dryness on the Tongue and Palate; but especially if we discover Risings or Swellings behind the Ears, in the Groin, or other tender Parts of the Body; but this last, where it happens, is of Advantage to the Patient; for he says, in such a Case, the Plague is rarely Mortal, for then Nature has Power to dispel the Venom, and drive it from the most noble Parts; and then he recommends Bleeding; but if Spots appear upon the Body, he advises the Use of Emeticks, and afterwards Sudorificks, which, by his Papers, we find he gave with good Success, but he decries the Use of Opiates at the Beginning of the Distemper.

He concludes with Directing of proper Cordials, to refresh and strengthen the Patient, such as Confect. Hyacint., Confect. Alchermes, Pulv. Gasconiæ, Bezoar Orient. and such like.

But my Worthy Friend, Sir John Colebatch, who has in other Cases declared himself for Publick Good, has, in this, likewise been Careful to provide against the Infection, and especially recommends to his Friends, to collect large Parcels of the Ripe Ivy Berries which are known from the others by their Blackness.

Thus have I given my Reader such a View of the Plague in general, as may point out to him its natural Cause, Progress of Infection, and the Methods that have been used by the Learned, to prevent the spreading that Terrible Distemper.

FINIS