HEALTH ON THE ISTHMUS AND THE FUTURE OF THE WHITE RACE IN THE TROPICS
_Yellow Fever._
THE cities of Colon and Panama have never been particularly unhealthy to
the Panamanian born, whether white or coloured, or to the West Indian
stranger.
This population has merely been subject to the malaria common to
equatorial towns, especially when in the neighbourhood of swamps, and to
the evils which attend imperfect sanitation in a hot climate.
The intervening country is very malarious in the low-lying parts, less
so on the hilly divide, differing in no way from other similar
localities in the same latitude.
[Illustration: READING ROOM, EMPLOYEES' CLUB, CULEBRA.]
[Illustration: HALL OF EMPLOYEES' CLUB, CULEBRA.]
The reputation of the Isthmus of Panama as a death-trap is due to the
sickness which (previous to 1906) has always been prevalent among white
strangers, and most other visitors, and particularly to the high
percentage of death from yellow fever. To this short, sharp, and most
deadly disease the native-born is immune; hence the affairs of the city
of Panama have gone on well enough for centuries, as far as the
residents are concerned, except that travellers by the Isthmian route
tarried no longer than they could help. Whenever large numbers of
strangers have congregated on the Isthmus, as during the Californian
gold-rush, the construction of the railway, and the Canal construction
of the French Companies, there has been an epidemic of yellow fever
among them, and a very large proportion of cases have terminated
fatally.
The immunity which the West Indian negro enjoys from this disease gave
him a superiority over other labourers on the Isthmus which, since the
extinction of the disease, is no longer his.
During the American occupation of Havana, after the American-Spanish
War, yellow fever broke out among the strangers, and the mere cleaning
up of the city, though carried out with military thoroughness, had no
effect in checking the disease. A medical board was sent to study the
matter. This was in 1900, four years after Major Ronald Ross, of the
Indian Medical Service, had discovered the cause of malaria. Ross had
proved that the cause of malaria in man was the presence in his blood of
an organism introduced by the attack of the _anopheles_ gnat (or
mosquito), and that the species was only poisonous to man if it had
itself become infected with the germ of this organism in biting a man
suffering from malaria. Thus man and _anopheles_ act alternately as
hosts to the organism, which apparently requires their co-operation for
the continuance of its species.
Gnats, or mosquitoes, as they are indifferently termed, being thus under
more than suspicion as an immediate cause of tropical fevers, the
medical board turned their attention to them, and Mr. Reed, a member of
the board, tracked the yellow fever to another gnat, the _stegomyia_,
and, aided by the heroic devotion of his assistants, proved beyond
shadow of doubt that this disease is due to the activity of another
minute organism, which lives a double life in man and _stegomyia_. Mere
contact with the clothing, &c., of yellow-fever patients was proved to be
no source of infection.
The _stegomyia_ lives three months. It becomes dangerous only by
imbibing the organism through attacking man during the first three days
of yellow fever, and, even then, twelve days elapse before its bite is
infectious. Six days after a man has been bitten by an infectious
_stegomyia_ he develops yellow fever, and for the next three days (as
has been already said) he is infectious to the _stegomyia_.
During the American occupation of Cuba attempts were made to obtain
immunity from yellow fever, but it was found impossible to regulate the
disease when voluntarily communicated by the bite of the mosquito, and
at present immunity is only enjoyed by persons who inherit the
privilege.
The _stegomyia_ does not breed in open swamps or large bodies of water,
but needs shelter, and is also incapable of sustaining a long flight. It
breeds chiefly in and near towns, depositing its larvae upon the surface
of cisterns or stagnant pools.
Colonel W.C. Gorgas, M.D., took charge of the Department of Sanitation
of the Commission in July, 1904. "The experience of our predecessors,"
he writes,[27] "was ample to convince us that unless we could protect
our force against yellow fever and malaria we would be unable to
accomplish the work."
[27] "Sanitation in the Canal Zone," by W.C. Gorgas _Journ. Am. Med.
Assoc._, July 6, 1907, vol. xlix.
[Illustration: READING ROOM, EMPLOYEES' CLUB, CULEBRA.]
[Illustration: HALL OF EMPLOYEES' CLUB, CULEBRA.]
At this time there was but little yellow fever on the Isthmus, and, in
spite of the arrival of a large number of non-immunes, no alarming
outbreak occurred during the first ten months. During April, 1905,
however, the administration building in Panama, in which worked some 300
non-immune employees of the Commission, became infected. In that month
there were 9 cases and 2 deaths; in May, 33 cases and 8 deaths, of which
21 cases and 2 deaths were among employees of the Commission. In June
there were 19 deaths from yellow fever on the Isthmus, and in July 13.
The Commission reported[28] that:--
"A feeling of alarm, almost amounting to panic, spread among the
Americans on the Isthmus. Many resigned their positions to return to the
United States, while those who remained became possessed with a feeling
of lethargy or fatalism, resulting from a conviction that no remedy
existed for the peril. There was a disposition to partly ignore or
openly condemn and abandon all preventive measures. The gravity of the
crisis was apparent to all."
[28] Annual Report, 1905, p. 30.
Colonel Gorgas writes[29] of this time:--
"We could readily see that if the conditions as they existed in 1905
were to continue the Canal would never be finished."
And he adds that:--
"The Executive Board of the Commission itself, as late as June, 1905,
stated that the sanitary work of the Isthmus had been a failure and
recommended that the _personnel_ be changed and other methods tried. But
the Supreme Authorities ... gave us steady support, and by the following
December yellow fever had disappeared from the Isthmus."
[29] "Sanitation in the Canal Zone."
The total deaths among employees of the Commission from yellow fever
during the 12 months October 1, 1904, to September 30, 1905, was 37,
among about 17,000.[30] The total from yellow fever among the whole
population, including Canal employees, during the four months May 1 to
August 31, 1905, was 47, while the number of deaths from malaria during
the same period was 108. The effect of malaria in impairing physical
efficiency was even more in excess than these figures indicate, for the
fatal cases are a small proportion of the whole in malaria, and a very
large proportion in yellow fever. The moral effect of the imminence of
the more sudden and fatal form of disease was, however, as these reports
show, much the greater, and it was this moral effect which caused the
crisis above described.
[30] In 1883-84 the French Company lost by yellow fever 66 men out of
about the same number of employees.
* * * * *
Previous to February, 1905, the Department of Sanitation had done little
to improve the hygienic conditions of Colon and Panama, chiefly owing to
the opinion until then maintained by the legal advisers that there was
no authority to expend money in those cities, which are not within the
Canal Zone.
In April the yellow fever broke out; the number of men employed by the
Department of Sanitation was increased to the huge total of 4,100, and
the battle with yellow fever began in earnest. All cases were either
transported to screened buildings, or, if left in their own homes, these
were carefully screened with fine-meshed copper gauze. The object of
this isolation was to prevent the patient from infecting healthy
_stegomyia_ mosquitoes.
Every dwelling in Colon and Panama was thoroughly fumigated with
pyrethrum powder or with sulphur, and then cleared of dust and refuse,
which, with the insensible but not always dead mosquitoes, was then
burnt. The complete, and, it is hoped, final freedom from yellow fever
in Colon and Panama has been obtained by means of a proper water supply
and universal paving with brick or cement, as well as the supply of
proper drainage. Formerly water for domestic use was stored in cisterns,
tanks, tubs, jars, and so forth, and, after rain, water stood stagnantly
in a thousand ruts and holes in the unpaved squares, streets, and lanes.
These breeding-places of the _stegomyia_ have now been done away with
completely in Panama, and almost completely in Colon. The latter city is
so low-lying and flat, and subject to such heavy rainfall, that pools of
stagnant water will form. They can, however, be oiled, which kills the
larvae, and, moreover, it is Panama, and not the wind-swept,
salt-saturated, town of Colon, which has been the chief source of yellow
fever.
The last case of the disease in Panama occurred in November, 1905, and
in May, 1906, there was an isolated case in Colon. The infection is
considered to be at an end in a city three months after the last case,
that being the lifetime of _stegomyia_. After this period, all infected
_stegomyia_ having died, those that remain are powerless for harm.
Nevertheless, the stringent measures for their destruction are not
relaxed, as, while _stegomyia_ exists, the germ, if re-introduced, will
be rapidly disseminated.
Thus the yellow fever, having taken toll for four hundred years of those
who crossed the Isthmus, has been completely eradicated by. Colonel
Gorgas and his assistants. It is a triumph of science and of despotic
government combined; and only in this combination can preventive
medicine achieve full success.
There is one other aspect of the yellow fever campaign which must be
mentioned before going on to describe the fight with malaria.
Yellow fever, unlike malaria, does not occur in all tropical countries.
Its home is the West Indies, Central, and parts of South, America, and,
before its extinction in Havana, it has been a serious scourge in the
Southern United States. In the New World cases have occurred as far
north as Quebec, in Europe cases have occurred in Wales and France, and
there have been serious epidemics in Spain. It has never been known east
of Genoa, whether in Europe or elsewhere. Thus in Africa it is known on
the west but not on the east coast. The fact that it is unknown in India
is very remarkable, seeing that _stegomyia_ is a very prevalent variety
of mosquito there. It follows from this that if yellow fever once got
hold in India it would probably spread and might work great havoc. The
same is true of China in an even greater degree, for such preventive
measures as have been taken in Panama would be far more difficult to
carry out in the great cities of India, and altogether impracticable in
those of China. Thus, as Colonel Gorgas has pointed out, if the Canal
had been constructed in spite of yellow fever, and if that disease had
been allowed then to persist at Panama, the disease might not improbably
have been carried to Asia, for the three months of life of _stegomyia_
is ample for the voyage. In this event the Panama Canal might have
proved a curse rather than a boon to mankind.
[Illustration: CUT SOUTH OF CULEBRA, LANDSLIP ON LEFT.]
[Illustration: LOOKING NORTH, THE SCARPED FACE OF GOLDEN HILL ON THE
RIGHT.]
_Malaria._
The campaign against malaria has been conducted on somewhat different
lines. The _anopheles_, which transmits that disease, deposits its larvae
in clean water where grass and algae grow, and is therefore almost
entirely a mosquito of country districts. But Colon and Panama, both
small cities, are exposed to the disease, as are about seventeen little
towns and forty villages for labourers along the line of the Canal. As
the flight of _anopheles_ is not more than one hundred, or possibly two
hundred yards, the working population can be in great measure protected
from their attack by destroying the breeding places for such a distance
on either side of the dwelling and working places. This in itself is a
large task, which could not be carried out in a short time, and while in
progress the Sanitary Department relied mainly upon the erection of
buildings completely screened (including the verandahs) with fine copper
gauze, which effectually shields the employees against mosquito attack
within doors, and therefore during the particularly dangerous hours of
night.
In addition, the employees are supplied with quinine, and recommended to
take three grains daily while in health. This "cinchonises" the blood
and renders it unwholesome to the malarial parasite.
The effect of screening is shown by the following example from the
report of the Commission, December, 1906:--
"The first shipload [of European labourers] arrived during the dry
season, when mosquitoes were most scarce, and were quartered in
unscreened buildings. Within six weeks of their arrival 33 per cent. of
these labourers had been taken sick with malaria. The second shipload
arrived during the rainy season, and were quartered in a camp not 200
yards distant from that of their predecessors. The buildings of the camp
were screened. Sickness among the men was infrequent, and when they had
been upon the Isthmus six weeks it was found that only 4 per cent. had
found their way to the hospitals."
* * * * *
The destruction of larvae, and of their hiding places, is commenced by
the clearing of grass and bushes, which are cut down with the _machete_,
a short cutlass with which the Panamanian is very expert, _machete_ work
being, indeed, the principal _role_ in which the Panamanian is employed
by the Commission. Also ditches are cleaned out, and heavy oil poured
upon the water in trenches and pools, and land-crabs are caught and the
holes in which they dwell are filled in or oiled. Finally the soil is
drained, which is the only means of making the ground permanently unfit
for mosquito breeding. Subsoil draining is the best, a tile drain being
put in; for, even in concreted gutters, pools will form, owing to
accidental obstruction, and remain sufficiently long for the deposition
and hatching of the larvae. Such is the work of the _anopheles_ brigade,
and the _stegomyia_ brigade carry out similar operations, in the
neighbourhood more particularly of Panama.
With regard to the effect of these operations upon the numbers of the
mosquitoes I may narrate my own experience. I arrived at Colon first in
January, 1907, and spent one or two nights on board my ship. This was
two years and a half after the commencement of the mosquito campaign,
and the officers of the ship congratulated themselves upon the absence
of the swarms of mosquitoes which formerly attacked them at night on
their vessel. I found, however, that although there was no swarm of
mosquitoes, such as I have seen, _e.g._, when on board ship in the
harbour of Colombo, Ceylon, yet that the individuals who remained
certainly caused me discomfort, and I think some subsequent
indisposition. In April, 1908, however, during two days at Colon, I did
not so much as see a single mosquito.
[Illustration: LOOKING NORTH FROM RAILWAY BRIDGE AT PARAISO.]
[Illustration: ABANDONED FRENCH MACHINERY.]
At Panama, in January, 1907, my wife and I stayed in the Commission's
screened hotel on Ancon Hill, not caring to face the dirt and squalor
of the old city. In April, 1908, finding the city properly paved,
drained, and plumbed, we took up our quarters at the Hotel Central in
the town, where we spent a fortnight in perfect health; and although
this building, not being under the Commission, is unscreened, I was only
bitten by mosquitoes, to my knowledge, twice during that time, and this
without subsequent ill effect. I may add that the picturesque
surroundings, not unlike those of some city on the Mediterranean,
greatly enhance the pleasure of a stay on the Isthmus, now that they can
be enjoyed without squalid accompaniments. I did not, except on one or
two nights, even draw the mosquito curtains. Out of doors, in the city
of Panama, I was not bitten once, though I was attacked once or twice by
solitary mosquitoes when walking on roads or paths with shrub or jungle
adjoining. This was near the end of the dry season. When the rains
commence a greater number of mosquitoes must be expected.
Natives of the Isthmus and the West Indies are not immune from malaria,
and in 1904-5 about one-half of the inhabitants who were examined
proved to have the parasite of malaria in their blood. As the
_anopheles_ becomes infectious through biting a malarious man, it is
evident that such a dissemination of the parasite throughout the blood
of the human population renders mosquitoes especially dangerous. In the
same proportion as the population becomes less malarious, so the
mosquitoes become less dangerous, and theoretically a millennium is
possible in which man and _anopheles_, mutually purged of the malarial
organism, may live happily together. Unfortunately, a malarious man it
is believed remains infectious to _anopheles_ for no less than three
years, instead of the three days' limit of yellow fever, and this
greatly increases the difficulty of exterminating malaria.
During 1906, with a force of 26,000, there were 21,739 cases of malaria
admitted to the Commission Hospitals, and the death-rate from this
disease was among whites 2 per thousand, among negroes 8 per thousand.
In 1907, with a force of 39,000, there were 16,753 cases, the death-rate
among whites being 3 per thousand and among negroes 4 per thousand. The
increase among whites was due to the greater proportion of the European
labourers, whose circumstances are different from those of the skilled
artisans and the "screened" clerical staff of Americans.
The total death-rate from all causes in 1907 is shown below:--
---------------------------------------------------------
| Average | Total | Annual Death
| Number. | Deaths. | Rate per
| | | Thousand.
--------------------+---------+---------+----------------
White Employees | 10,709 | 179 | 16.71
Black Employees | 28,634 | 953 | 33.28
|---------+---------+----------------
Total | 39,343 | 1,132 | 28.77
---------------------------------------------------------
--but accidents account for a considerable proportion of the deaths.
During the same period the average number of American women and children
in Commission quarters was 1,337, among whom occurred nine deaths, an
average annual death-rate of 6.73 per thousand.
In addition to malaria there is one other disease which proves fatal to
considerable numbers of employees, attacking principally the black
labourers. This is pneumonia, to which are attributed altogether 328
deaths as against 154 from malaria.
It appears that special research is needed into the cause and prevention
of this disease among negroes in the tropics.
* * * * *
In 1907 no less than 71,000 persons arrived on the Isthmus, all of whom
had to pass the Commission doctor at the entrance port. All but
transients are vaccinated on arrival, and great watchfulness is
exercised against the introduction of any new disease from abroad. Thus,
when bubonic plague broke out at Guayaquil, the Department of Sanitation
commenced a campaign against rats as a precaution against the spread of
the disease (which is propagated by the rat flea) in case quarantine
measures failed to keep it out.
Again, when one or two cases of rabies recently occurred on the Isthmus,
all dogs for whom an owner could not be found were at once destroyed.
_Life on the Isthmus, and on the Future of the White Man in the
Tropics._
The Canal Zone now being healthy, the life of the Americans is a
cheerful as well as a busy one. The climate, to which the local diseases
used to be attributed, is not by any means wholly bad. There are really
two climates, that of the Atlantic seaboard and that of the Pacific
side. Colon is somewhat trying on account of the humidity, but a healthy
trade-wind blows. The town of Panama, though receiving much less rain,
is also somewhat humid, owing to there being less breeze. The
temperature, however, is lower than that of the great cities of the
United States, even in the North, during summer heat-waves, the hours of
sunshine are shorter, and the general feeling of oppression is, I think,
distinctly less. The Ancon suburb, where the Commission buildings are
situate, is free from the humidity of the low-lying city. The high lands
at or near Culebra, where a large part of the American population now
resides in screened wooden buildings, enjoy in the dry season a bracing
climate, a fresh dry wind blowing across the divide, imparting a sense
of exhilaration, which is heightened by the fine scenery, the pleasant
scents of the surrounding woodland, and the ordered activity of the
life. Amidst such circumstances the Canal official finds it easy to work
hard. I noticed in this a great contrast to the condition ten years ago
at Ismailia, the headquarters of the Suez Canal Administration. This
place, before Major E. Ross's discoveries, suffered severely from
malaria, and the officials of the Administration, some of whom had
resided there for twenty years or more, were in many cases saturated
with malarial poison. Work for them was a burden, bravely borne indeed,
but taken up each day with a sigh. I spent about a fortnight there in a
hot season conducting some investigations upon the forms and movement of
drifting sand-dunes. I suffered during part of the time from fever, and
only kept on working with an effort, whereas on the Isthmus I enjoyed
more than usual vigour. At Culebra, indeed, the dry season is so bracing
that the arrival of the rains is welcome for the soothing effect of
greater humidity, as well as on account of diminished dust. The white
woolly cloud or mist which then wraps round the hill-tops is no longer
the "white death," as it was called in the days of the French Company,
when the vapours were credited the poison which really lurks in the
mosquito. Even now, however, there is an increase in the number of
mosquitoes, and some increase in malaria, when the rains come.
[Illustration: GANG OF EUROPEAN LABOURERS (IN 1907).]
[Illustration: A FORMER HOT-BED OF MALARIA, NOW DRAINED.]
Not only do the men look well, but the women and children also. The
women in general have the same appearance as in the United States;
perfectly dressed, as always, quiet in manner, and apparently happy,
though occasionally somewhat bored. To the wife, not having the
absorbing interest of the Canal work, the Isthmus is generally less
interesting than to her husband, but of late there have grown up
organisations for promoting intellectual and other social intercourse
which are rapidly relieving the threatened ennui.
The children, on the other hand, look actually happier and stronger than
they do in the cities of the United States. They are in the open air all
day, for sunstroke is rare on the Isthmus; they are bronzed, active,
fearless in bearing, and apparently thoroughly satisfied with themselves
and with their surroundings. Even when within doors they are still in a
sense in the open air, for the windows are unglazed, and the houses are
constructed so as to secure a free circulation of air.
It has been said that the possession of India taught the English the
value of the cold bath, an institution which has been slowly adopted
from us by other Northern nations in Europe. Perhaps the possession of
the Canal Zone will lead to the salutary open-window habit, which is not
yet general in the United States.
The Commission clubs for gold-employees at the principal stations are
commodious structures, admirably designed for social recreation; their
management is entrusted to the Young Men's Christian Association. There
are well-equipped reading and writing rooms and gymnasia, mainly used by
the men, but the interests of the women and children are not neglected,
and for the last playrooms are provided. The large halls are used for
entertainments and for meetings of the numerous benevolent "secret"
societies which have been so important a factor in the preliminary
organisation of American society in newly settled territories. In the
clubs only "soft" drinks are provided, but I can testify to their
excellent effects.
The question whether the white race can make a home in the tropics
depends ultimately upon the tropical baby--upon his own health and that
of his mother. The American occupation is still recent, but as far as
experience goes it seems that the white children born on the Isthmus
have not shown unusual delicacy, and the mothers have made a normal,
though sometimes rather slow, recovery from confinement.
The views of Colonel Gorgas upon the future of the white race in the
tropics deserve quotation. He writes[31]:--
"I think the sanitarian can now show that any population coming into the
tropics can protect itself against these two diseases [malaria and
yellow fever] by measures that are both simple and inexpensive; that
with these two diseases eliminated life in the tropics for the
Anglo-Saxon will be more healthful than in the temperate zones; that
gradually, within the next two or three centuries, tropical countries,
which offer a much greater return for man's labour than do the temperate
zones, will be settled up by the white races, and that again the centres
of wealth, civilisation and population will be in the tropics, as they
were in the dawn of man's history, rather than in the temperate zone, as
at present."
[31] "Sanitation in the Canal Zone."
In this connection I may perhaps be permitted to refer to an interesting
suggestion made in the course of conversation by Colonel Gorgas,
although I omitted to inquire if it had been published. This suggestion
was that the records of the movements of great armies under the rulers
of ancient Mesopotamia and Egypt indicate that malaria did not then
exist in the nearer East, and that malaria, like yellow fever, was once
a local disease.
[Illustration: NEAR THE SITE OF MILAFLORES LOCKS.]
[Illustration: LOOKING NORTH TO CULEBRA DIVIDE FROM ANCON HILL.]
From what I have seen as tourist and traveller (not as resident) in the
West Indies and in the Orient, I have arrived at the following tentative
conclusions, viz.:--
That the debilitating effect which the tropics have been observed to
exercise upon those who come from temperate regions has been due mainly
to the presence of certain diseases which can be done away with.
That the rapid deterioration of the white stock which is usually noticed
in the tropics, especially near the equator, is mainly due to the same
cause.
But that Anglo-Saxons cannot perform nearly the same amount of hard
bodily labour in a constantly hot climate as they can in the temperate
zone, and Anglo-Saxon immigrants never will be able to do so. In this I
think the Mediterranean races--at all events the Spaniards and
Italians--are our superiors.
Whether the descendants of Anglo-Saxon stock who have settled in a
tropical country purified from tropical diseases will be able to support
continued hard bodily labour better than their immigrant ancestors is a
matter about which we have at present no direct evidence.
It may possibly be worth noting, however, that some years ago, when
wintering in Manitoba, I found that some of the farmer immigrants from
England felt the cold more as the years went by, but that their children
born in the country were unaffected by it.
It is the case that in the tropics, particularly in the equable
equatorial belt, many evils of the temperate zone are avoided, chiefly
those due to cold and to sudden changes of temperature. It is this
equatorial belt of equable temperature and heavy rainfall that I chiefly
have in mind, for it comprises those vast regions of prolific vegetation
which appear capable of supporting so large a population.
The white man already rules, or has marked off for rule, the whole of
the equatorial belt, but who is to be the peasant cultivating this belt?
In those parts of tropical Asia already peopled by industrious Orientals
there can never be a white peasantry. Equatorial Africa presents great
differences in different parts with respect to native population, and
the question of a possible future for white peasantry is there a
complicated one. In South America, however, there are vast equatorial
regions either wholly unpeopled, or sparsely inhabited by tribes of that
Indian stock which has elsewhere proved so slight an impediment to the
establishment of the white labourer. Served by a system of rivers
unrivalled elsewhere in equatorial regions, already partitioned among
Christian Governments, and for the most part uninhabited, the forests
and savannahs of Equatorial South America offer the readiest field for
the establishment on a vast scale of a white peasantry under the
equator.
By clearing the scrub within one or two hundred yards of his cottage,
and by employing wire screens, the cultivator can protect himself
against malaria, and his crops come not once, but several times a year.
If the Spanish, Portuguese, and Italian peasant were to turn his
attention to this field, instead of, or in addition to, that of navvy
work, great things might come of it. The circumstance that South America
is a Roman Catholic continent, where the Latin races are dominant, would
enormously favour the experiment. On the Zone, the Spanish labourer
works in order to save and to depart, the _milieu_ being foreign to him
and unattractive. In a Latin State it would be different.
In writing of the possibilities of the white race in the equatorial zone
it is understood that the problem relates to the lowlands. There are, of
course, favoured highlands, such as those of Colombia, where the
temperature is at the same time moderate and equable and the climate
appears admirably adapted to white men.
A healthy city life in the tropics would be easily attainable in a new
country settled wholly by white people and under a medical despotism.
The general, but non-specialist, opinion upon the Isthmus is not as
sanguine as that of Colonel Gorgas upon the hygienic future of the white
race in the tropics. The general opinion among Americans seems to be
that, as far as they are concerned, they would, if engaged in the
tropical parts of South or Central America, avail themselves of the
improving means of transit to revisit frequently the United States, and
would rely upon such vacations in higher latitudes for the retention of
their native vigour.