Kitabı oku: «Observations on the Diseases of Seamen», sayfa 9

There is reason to think that the open air very soon dissipates and renders inert all infections of the volatile kind, and of course the warmer the air is the more readily it will have this effect. It is accordingly observed, that infection is much less apt to be generated about the persons of men, and that it adheres to them for a much less space of time in a hot climate than in a cold or temperate one. This is a remark, which, so far as I know, has not been made by any author; and, till observation suggested it to me, I fancied the reverse to be the truth. I have seen so many instances of filth and crowding in ships and hospitals in the West Indies, without contagion being produced, and which in Europe could hardly have failed to produce it, or to render it more malignant, that I am convinced there is something in tropical climates unfavourable to the production and continuance of infectious fevers⁵³. The ships which bring this fever from Europe in general get rid of it soon after arriving in a warm climate; and nothing but the highest degree of neglect can continue or revive it.

The facts above mentioned brought into my mind what is related of the plague at Smyrna and other places, that it disappears at the hottest part of the year. It is also curious and important to remark, that the true pestilence never has been heard of between the tropics. It is not easy to assign the cause of this effect of heat upon infection, as every thing relating to this subject is very obscure. We can conceive it to be owing to the greater degree of airiness which the heat of the climate makes necessary, or to the use of fewer woollen clothes. There may be something in the state of the body, particularly in the pores of the skin, which disposes them less to imbibe or produce the poisonous effluvia, or, when imbibed, it may more readily be thrown out by perspiration with the other acrimony of the blood; or more probably, as has been hinted above, the virulent matter is of such a degree of volatility as to be readily dissipated in a certain degree of heat⁵⁴.

There is a fact, which, though seemingly of a contrary tendency, yet is in reality in proof of the same opinion. It is, that these same diseases disappear in circumstances of great cold. When England was last visited by the plague, it disappeared in winter; and the same is observed at Moscow and other places. In this case the infectious matter is rendered inert, but not extinct, and the return of heat sets it afloat in the atmosphere, so as to expose it to human respiration. Dr. Guthrie informs us, that infection is entangled and fixed by the cold of winter on the doors and walls of the houses of the Russian peasants, and that upon the return of the warm season it is set loose by the thaw, and then becoming active, produces diseases.

With regard to the West Indies, the precautions that have been laid down are chiefly necessary when a ship newly arrives in the climate; for it is during the first three or four months that sickness is apt to prevail.

This does not depend upon any thing peculiar to the climate; for I have known ships arrive without being visited with any sickness. It seems to be owing, for the most part, to that flock of infection and disease imported from Europe exerting its effects, and when this has spent itself, the men remain in good health, unless exposed to the land air or other accidents; for the air at sea in those climates, as well as every where else, is extremely pure and wholesome, and there is no where that seamen are more healthy or comfortable.

SECT. III.
Of the Foul Air generated in a Ship

I mean here to distinguish the unwholesome vapour produced by the contents of the ship from the infection produced by the effluvia of men’s persons, which was treated of in the last section.

The means of preventing this foul air from being generated are, cleanliness, dryness, and ventilation.

All parts of a ship may, if neglected, become dirty, and emit an offensive vapour; but the parts under water consisting of the orlop and hold, are more particularly so from the materials they contain, and from the want of free access to the fresh air; accordingly, there is always more or less stench in those parts, even in the best-regulated ships.

It was mentioned in the first part of this work, that an opinion was entertained by some that no foul air was productive of fevers but such as proceeds from the living human body. I alledged that this was otherwise, at least in hot climates; and some proofs of this opinion were adduced, particularly from the French prizes. Though the neglect of personal cleanliness is the principal source of disease, yet cleanliness of every kind, and purity of the air in every respect, is to be anxiously studied.

With regard to general cleanliness, it is hardly necessary to mention sweeping, washing, and scrubbing of the decks; for the natural propensity of the English⁵⁵ nation to neatness seldom allows any neglect of these. Lord Howe, to whose virtues as a man, and abilities as an officer, his country is so much indebted, gave it in general orders to wash the upper decks every day, the lower decks twice a week, and the orlop once a week at least. He also ordered that, every washing, smoking, mustering, and review of clothes, or any other means taken for the health of the ship, should be marked in the logbook, and the reason to be assigned there if omitted at the stated times. These rules are a good specimen of the order that ought to prevail in every branch of public duty; for it is well known to every experienced officer that it is a methodical proceeding of this kind which can alone render service either easy or effective.

The loss of men’s lives from the foul air of the well is a common accident in ships, and I have been myself witness to several instances of it. Where there is the least suspicion of this, a candle should previously be let down, and if it should be extinguished, it may be concluded that the air is deadly. It becomes safe for men to breathe in it by leaving it open for some time, or, more expeditiously, by letting down fire in a pot or grate, which soon changes the air, by producing a draught of it upwards.

It is a very salutary practice to let down fires frequently into the well, both in order to purify the air and to dry the surrounding parts. It was formerly mentioned that this was daily done in the Intrepid, and the effect of it was to remove the wetness of the ballast and the mouldiness which had overspread the sides and beams; and having had the effect of sweetening and purifying the air, it seemed to be the principal circumstance that tended to make this ship extremely healthy from being the most sickly of all the fleet. This precaution, as well as every other point of cleanliness, is more necessary in large ships, because the mass of foul air, as well as the quantity of corrupting materials, is greater⁵⁶.

The following fact strongly evinces the good effect of fire and smoke: – When it was the custom for frigates to have their kitchens between decks, they were much more healthy than in the present construction, in which they have them under the forecastle, where the heat and smoke are dissipated without being diffused through the ship, and causing a draught of air upwards, as formerly. The men derived then also great benefit and comfort from having a large fire, round which they might assemble to warm and dry themselves in a sheltered place. I leave it to those who preside in the construction of the navy to determine how far it would be advisable to return to the old manner of construction. The French ships of the line have their kitchens and ovens between decks, and this must tend to counteract the effects of their want of cleanliness. The Dutch ships of the line have their kitchens on the orlop deck, which must be still more conducive to the general purity of the air.

Moisture is pernicious both in itself and as the instrument of putrefaction. All the complaints, called colds, are more owing to wet than cold; and moisture may be the means of producing, or at least of exciting dangerous fevers, when they would not otherwise appear. It besides contributes greatly to the production of scurvy. Ships built of ill-seasoned wood are found to be very unhealthy on account of the moisture contained in it. The moisture of timber arises not only from being used too soon after being felled, but also, as I am informed, from being stripped of its bark and outer surface when piled and exposed to the weather in dock yards. This method of smoothing and piling the wood is only a late practice; and the advantage in point of convenience and neatness seems to be more than overbalanced by the detriment it thereby receives.

A wet hold diffuses moist vapour all over the ship; and it was a rule with some of those commanders whom I observed to be most successful in preserving the health of their men, not only to have daily fires in the well, but to bail out the water when the pumps could not exhaust it all, and never to allow it to collect to more than the depth of a few inches. It is, therefore, very doubtful whether it is a good practice to let in water, as is very commonly done in order to sweeten the hold, for the same sweetness will be preserved if it is kept strictly dry. If it should happen, indeed, that there should be a great deal of putrid matter in the lower parts of the ship, from previous neglect or unavoidable leakage, it may be adviseable to let in a quantity of water in order to loosen and wash off what is offensive, and then to pump it out.

There is a circumstance in the first fitting out of a ship well worth attention, as highly conducive to the dryness and cleanness of the hold. I mean the choice of the ballast; for that which is called shingle, consisting all of pebbles, is far preferable to that which is sandy and earthy, as it does not so readily soak and retain the moisture and filth. Water or fluid of any kind readily subsides in it, and should any putrid matter be entangled in it, there will be less difficulty in washing it out.

The decks should not be washed so often when the weather is moist as when it is fine, as it will be more difficult to dry them, and more harm may arise from the moisture than benefit from the cleanness. Washing should also be performed very early in the morning, even in the best weather, in order that there may be time for the decks to become dry in the course of the day. It is after a general washing that the moveable fires, formerly described, are most proper and useful.

Every contrivance should be fallen upon to change the air in the orlop and hold. Ventilators and windsails⁵⁷ are well adapted for this purpose, and should be used as frequently and for as long a time as possible. It has also a good effect in cooling the air in the lower parts of a ship in the West Indies, to lift the gratings of the hatches, raising them on their edges, and lashing them to the staunchions. It contributes likewise to cleanliness and coolness to keep the decks as clear as possible from⁵⁸ chests and other lumber, which are in the way of sweeping and washing, and prevent also the free course of the air.

Particular attention to ventilation is necessary in frigates, for almost all that part in which the men sleep is excluded from the air, and they are therefore very uncomfortable in the West Indies unless small scuttles are cut in the sides. But if this should be objected to as weakening or endangering the ship, there is a good contrivance for the same purpose, which I met with on board of the Nymphe frigate. It consists of a square wooden pipe, of about nine inches in the side coming from between decks, running along the side of the ship, and opening over the gunwale of the forecastle. There was one on each side.

SECT. IV.
Means of guarding against Infection and Bad Air

Infection never prevails to such a degree, as to affect every person indiscriminately who is exposed to it. Even where the plague and small-pox prevail to the greatest degree, there are some persons who, though susceptible of these diseases, yet escape them. There are certain other infections of a weaker nature, as was before observed, and these will remain entirely inactive, till they find constitutions so disposed as to be fit subjects of their action. The seeds of disease may be compared to those of vegetables, which lye dormant, unless they happen to fall into a situation peculiarly adapted for exciting their activity. It is very difficult to account for this uncertainty in the operation of infection, but it is extremely providential, that under the most calamitous state of sickness, there are always some who are in health and who survive, for the necessary purposes of life. If this were not the case, it might happen that every person on board of a ship might perish from sickness in the course of a voyage, a circumstance which I believe has never been known to happen.

There is an endless variety in the constitution of the human frame, both in mind and body, as well as in the features of the face. There are, perhaps, no two individuals in the world in whom the same effect precisely is produced by the same food, air, medicine, poison, or passions of the mind. The different effects of infection, therefore, upon different people, seem to depend, in many cases, on peculiarities of constitution too obscure to be explained; but there are also known circumstances which resist or encourage its effects.

The great power of habit⁵⁹ in taking off the effect of infection, has already been mentioned, and it would appear that novelty gives an increased energy and activity to all impressions, as well as those on the senses. If a person, therefore, escapes the first attack of infection, he will be more likely to continue exposed to it with safety in future.

There are certain precautions necessary to be attended to by those who are unavoidably exposed to contagion, particularly in the first instance. Those who can afford a full diet, and a liberal use of wine, have been observed to resist infection better than those who use food and drink that is meagre and watery. It is also a good rule not to go among the sick, nor otherwise to expose one’s self to infectious air, with an empty stomach; for whether it is that the body is then more susceptible, or that the pores of the skin and lungs are in a more highly absorbing state, so as with greater readiness to inhale the poison of disease, it is certain that a person in that situation is more apt to catch harm from foul air of any kind. Whatever else weakens and exhausts the body, renders it also more susceptible of noxious impressions. Under the head of weakening powers, I comprehend not only what empties the body of its fluids, such as loss of blood, or a diarrhœa, but intoxication, fatigue, fasting, watching, and certain affections of the mind, such as care and grief.

Cold and moisture may also be enumerated among the causes that invite the attack of infectious diseases. They are of themselves simply productive of catarrhs, rheumatisms, and the like disorders; but if an infection should be accidentally present when the body is exposed to them, then instead of these complaints, the disease peculiar to that infection will be produced⁶⁰. This was illustrated in the last reinforcement we had from England; for while bad fevers were breaking out in most of the other ships, the ⁶¹Union was affected with those complaints only which are simply the effects of cold and moisture. It would be more proper, perhaps, to say, exposure to the air, than to call it cold; for exposing the naked body to the open air, even in the warmest climate, is prejudicial to health. This holds at least with regard to Europeans who are accustomed to clothing, however the natives of hot climates who are naked, may expose themselves with impunity.

It is of the greatest consequence to ascertain the extent of the influence of infection, for the means of avoiding and preventing it will very much depend upon this. It is now known, that infection extends itself to a very small distance. There are, indeed, some morbid poisons, such as that of the bite of a mad dog, and that of the venereal disease, which require actual contact to make them take effect. Others are more volatile, and seem to he inhaled by the breath, or absorbed by the skin, but these do not extend far. That of the plague⁶² does not reach above a few yards, and that of the small-pox and of fevers is probably equally limited. This discovery is very valuable, by ascertaining the limits of danger; for when a person imagines he runs the same risk when at a considerable distance from the seat of disease, as if he were in contact with the person affected, he will be apt to expose himself wantonly and unnecessarily to the infection.

It seems to be owing to the ignorance of the extent of its influence, that the plague has in general been so fatal; for in consequence of the opinion that the whole surrounding atmosphere was affected, it was vainly attempted to purify it by large fires in the open air, or by ⁶³firing off artillery, instead of trusting to the separation of the sick so as to avoid their near approach, and to the confinement of those in health to their own houses, which are all the precautions necessary to prevent its progress.

CHAP. II.
Of Aliment

SECT. I. Of Solid Food

The most unnatural circumstance in a sea life is the food which men use, and the disease most peculiar to it is one which is owing chiefly to the nature of the aliment; for though other causes conspire in aggravating the scurvy, the depraved state of the INGESTA is the main and fundamental cause of it.

It is this disease that is most fatal to seamen next to fevers. It was formerly as fatal, if not more so; but some modern improvements have rendered it less frequent and violent. The habitual use of salt provisions, besides producing evident symptoms of scurvy, begets such a state of the constitution, that, upon the least scratch being received, particularly on the lower extremities, a large and incurable ulcer ensues; and this circumstance, trifling as it appears, is the cause of losing an incredible number of men to the service, especially in the West Indies. The greater part of the food of a ship’s company is necessarily salted meat. Biscuit and pease, though of a vegetable nature, are hard of digestion; and though they qualify the animal food, they do not answer the purpose of fresh vegetables. Though officers have a supply of live stock even for the longest voyages, it would be impracticable to carry a quantity sufficient to preserve a whole crew from the scurvy. But certain articles have of late been introduced into use, of a durable and portable nature, which so qualify the salt provisions, that they can be used without inducing this disease. These are either such as are articles of common diet, viz. melasses and sour krout, or those which are intended only for the sick and recovering, such as portable soup and the preserved juice of lemons and oranges.

It is one of the most ancient and real grievances in the service, that there has not been a sufficiently ample supply of nourishment and cordials for the weak and recovering. This complaint is made by ⁶⁴Dr. Cockburn, who was physician to the fleet in the end of the last century; and it is a complaint that has not yet been entirely redressed, nor has the subject been considered with the attention it deserves. The only improvement in the sea victualling that I know of from that time till of late, has been the use of raisins for puddings, and the occasional use of vinegar, which is an article extremely salutary, and was looked upon as the great preservative of health in the Roman armies.

After the force of disease has been subdued at sea, men are frequently lost by relapses, or pine away in dropsies and other chronic complaints, for want of being supported by some cordial and nourishing diet. It is mentioned in my memorial to the Admiralty, how insufficient the small quantity of surgeon’s necessaries are; and it is recommended that a large quantity of certain species of refreshment should be put in the purser’s charge, which, being substituted for the common sea victualling while men are ill or recovering, would cost Government little or nothing. Besides the articles already mentioned, it was recommended to set apart a quantity of the best wines, and to be provided with brown sugar, dried fruits, barley, rice, sago, and salep. To these might be added eggs, which, if greased and put in salt, may be preserved fresh for a great length of time. Carrots and other roots might also be preserved for the longest voyages by means of sugar; and green vegetables might in like manner be preserved by means of salt. But of all the articles, either of medicine or diet, for the cure of the scurvy, lemons and oranges⁶⁵ are of much the greatest efficacy. They are real specifics in that disease, if any thing deserves that name. This was first ascertained and set in a clear light by Dr. Lind. Upon what principle their superior efficacy depends, and in what manner they produce their effect, I am at a loss to determine, never having been able to satisfy my mind with any theory concerning the nature and cure of this disease, nor hardly indeed of any other. An ingenious treatise has been published on this subject by Dr. Milman, to which I refer the reader, meaning to confine myself in this work chiefly to what is practical.

Every person who has beheld with attention and feeling the tedious and languishing series of suffering which the sick and recovering endure for want of the means of supporting and recruiting their strength and spirits, must wish that those who preside in the civil department of the navy would seriously consider this subject, and complete the reform that has already been begun.

With regard to the victualling of men in health, a most commendable attention has been paid to the improvement of it. The ordinary articles of victualling have not only been of excellent quality, but some new articles have been added, from which the greatest benefit has been derived. The chief of these are sour krout and melasses. The latter was first brought into use by Captain Ferguson in the beginning of the late war. He ordered it to be served with rice to the men who were affected, or threatened with the scurvy, in the ship under his command. The benefit experienced from it in this and other instances was so great, that during the last two years of the war it was made a regular article of sea victualling, and substituted in place of a certain proportion of oatmeal⁶⁶.

As bread is one of the principal articles of diet, the utmost care should be taken in preserving it, and great advantage would arise from stowing it in casks that are water tight, instead of keeping it in bags, or letting it lie loose in the bread room. Captain Cook, by this method, and by giving it a cast in the oven in the course of the voyage, preserved his biscuit found in every respect for more than three years. But the greatest improvement in this article of diet would be to have, in the form of flour, a greater proportion of what is now allowed in bread. The flour might be made into puddings, and seems, in this form, to be more nutritious and antiscorbutic than biscuit which has undergone a strong force of fire. This sort of mess would be still more proper and agreeable now that melasses is a stated article of diet. Flour, by being well pressed and rammed, will keep as long as biscuit, and it can be stowed in one fifth part of the space; it will, therefore, cost much less in freight than the same quantity of it in that form, and it may be baked abroad if necessary⁶⁷. Malt, by being well rammed, may also be preserved for a great length of time.

Of all the former articles of sea victualling, there was none more abused than oatmeal. The quantity allowed to each man was twice as much as he could consume, and the overplus went to the purser’s profits, or was wasted by being given to the hogs, or even wantonly thrown overboard. Melasses have, with great advantage, been substituted for part of it, in the proportion of eleven pounds for two gallons of oatmeal. The first trial of melasses was in the⁶⁸ Foudroyant, and it answered so well, that, in a cruise under Admiral Geary in 1780, this was the only ship free from the scurvy, and out of two thousand four hundred men that were landed at the hospital with this disease, there were none from this ship. It appears to be so similar in its nature and effects to essence of malt, that it seems hardly worth while for Government to be at the expence of providing the latter.

A certain proportion of barley has also of late been substituted for part of the oatmeal, which being more light and palatable, makes a pleasing variety, particularly to the sick and recovering. Captain Cook carried wheat with him, and found it to answer equally well. Might not potatoes also be a proper and salutary substitute, as they will keep a considerable length of time in a warm climate, and they have been successfully employed in their raw state for the cure of scurvy? It would not be right, however, to abolish oatmeal entirely; for there is a certain preparation of it which is an antiscorbutic of equal efficacy with any whatever, except the juice of lemons and oranges. This is flummery, or sowins, which is prepared by letting oatmeal and water stand together till they grow acidulous, and then boiling them into a jelly. I know of some well-attested instances of the crews of ships being saved from the scurvy by this alone.

Butter is a good article of victualling in so far as it renders that part of the diet which consists of grain and vegetables more palatable, and thereby induces men to eat more. But as it is extremely corruptible in a warm climate, hardly any being used by the seamen but what is more or less rancid, it should never be sent to a tropical station. Greater quantities of it are condemned than of any other article of victualling, and it is therefore the most expensive to Government. There are certain articles that are the natural produce of the West-India islands, which may be substituted for it with the greatest advantage. These are sugar and cocoa⁶⁹, which, during the last year of the war, were served in place of butter with great success, and this proved an alteration in diet not only salutary, but agreeable to the seamen, whose inclinations are always to be consulted in such changes⁷⁰.

When a ship is in port, encouragement should be given to the sale of roots, greens, fruits, and sugar. The men have a good custom of exchanging part of their bread, beef, and pork, for what they can get from the shore; but as they in general prefer spirituous liquors to the above-mentioned articles, the greatest care and vigilance should be used to preclude men from such opportunities of injuring themselves⁷¹. Every ship should be furnished with a seine, and other implements for fishing, when in harbour.

When captures are made, in which there are such articles as sugar, wine, rice, or fruits, it would be much better in many cases to allow the immediate use of them at sea, where the men may be disposed to scurvy or other diseases, than to wait for the conversion of them into money.

Though it has been my object to introduce as many articles of diet as possible, independent of salt provisions, it does not follow that these are in themselves unwholesome. They are pernicious by being made almost the sole and exclusive article; but if used in moderate quantity, they are even in some respects well adapted for the food of seamen. The nature of their life gives them a strong digestion: in their duties they not only employ violent exercise, but use more muscles and a greater variety of postures and motions than men of any other profession. To such constitutions may not food of a refractory nature and hard of digestion have even an advantage over what is more delicate and digestible?

It does not appear that it is the salt quality of the provisions used at sea that makes them productive of scurvy, but the want of their native juices and of the nutritious principle. A small quantity of salt is necessary to make all food palatable and wholesome, in so much that it is reckoned one of the necessaries of life. All animals have a craving for sea salt, and nature has kindly made it the most abundant and universal of all saline bodies. Food, without this seasoning, not only comes to be loathed, but the want of it renders the animal weak and flabby. As it not only assists digestion, but invigorates all the bodily functions by stimulating and bracing the fibres, it is in some cases a valuable medicine. It is remarkable that men are very apt to tire of a long continuance of fresh provisions⁷², but never of what is salt; and even under the scurvy the latter will be relished, and sometimes preferred to most other kinds of food. It has been a practice with some to make the scorbutic men drink sea water; but though it is not attended with any manifest benefit, I never heard that it aggravated the disease.

I was told by the gentlemen of the army at New York in 1780, that the soldiers in cantonments were not near so subject to agues as the people of the country; and the only difference in their mode of life was, that the former had in their allowance a certain, proportion of salt provisions.

In an unhealthy country I should think a free use of salt, as well as spice⁷³, would be salutary; and when ships are in port it would perhaps be better to allow a certain proportion of salt provisions, because it would not only be wholesome and agreeable, but the men’s constitutions would probably be more reconciled to an entire salt diet when necessary: but I would except from this the crews of such ships as have newly arrived from a long cruise or voyage, in which it may be necessary to alter the constitution as quickly as possible by a diet entirely fresh.