REPORT 
ON 
THE CLIMATE OF COLORADO, 
AND 
ITS RELATION TO PULMONARY DISEASES. 
CHARLES DENISOH, A.M., M.D., 
OF DENVER, COLORADO. 
EXTRACTED FROM THE 
TRANSACTIONS OF THE AMERICAN MEDICAL ASSOCIATION, 
PHILADELPHIA: 
COLLINS, POINTER, T05 JAYNK STREET. 
1 8 7 G. REPORT. 
In attempting a report of the kind I have the honor herewith 
to present, it is well to explain that the field for study is large, 
and the trail of investigation obstructed by many difficulties. On 
the one hand, there is the lack of complete meteorological records, 
with generally various understandings (or misunderstandings) 
of pathological facts by professional men. On the other hand, 
the comparatively recent development of this section of country, 
and the scarcity of statistics of carefully-recorded cases, combine 
to restrain the faithful reporter in undertaking so difficult a task. 
But with the facts, and both personal and professional experi- 
ence at hand, I hope to prove conscientious and impartial in the 
performance of this duty, even though it lacks the completeness 
attending more extended research. 
The Climate. 
To adapt the means—the climate of Colorado—to the end—the 
relief or cure of Pulmonary Diseases—a somewhat minute de- 
scription of what constitutes the climate of the Centennial State 
is necessary. We must consider all the conditions which make 
up the weather and atmosphere of this section. 
Topography. 
Colorado, situated between the 102d and 109th degree of lon- 
gitude west from Greenwich, and between the 37th and 41st de- 
gree of north latitude, covers an area of 105,000 square miles, 
being larger than the five middle States, or nearly as large as 4 
REPORT ON THE CLIMATE OF COLORADO, 
New England and New York, and has an average elevation of 
more than 6000 feet above sea level. That portion of the Ter- 
ritory traversed by the Rocky Mountain Range, together with 
the unsettled country west of the Range, it is not my purpose to 
refer to in this report. The plains and foothills east of the 
mountains, however, furnish a remarkable similarity in climatic 
attributes, and a sufficient field for a report of this kind. It is 
this section of Colorado, lying between the elevations of four 
and eight thousand feet above sea-level, to which I wish to 
be considered as herein referring, unless other localities are 
specified. 
This belt of land running north and south through Colorado, 
varies in altitude chiefly with the location of its few rivers. The 
Divide, a low ridge separating the waters of the South Platte on 
the north, and the Arkansas on the south, is between two and 
three thousand feet higher. These rivers and their branches 
come down from the mountains, and the elevated parks to the 
west, through rugged gorges or canons, and have for ages been 
depositing their washings which form the plains below. The 
region specified is remarkable for the absence of trees, except 
on the Divide, among the foothills and along the streams ; also 
for the growth of a short, fine quality of grass which covers the 
plains and cures as it grows. 
The sandy soil, impregnated more or less with alkali, favors 
radiation of heat and absorption of moisture, and to a certain 
extent influences the marked meteorological effects which are 
noticeable. 
.Temperature. 
The climate of this region is not equable except as compared 
with others of similar elevation. Generally speaking, equability 
decreases as altitude increases. The rarity of the air favors a 
rapid change of temperature. 
Thediurnal and annual variations are considerable, the elevation 
and exposure of localities having more to do with temperature 
than their latitude. Excepting differences due to these reasons, 
the isothermal lines run nearly north and south through the State. 
For instance, according to the report of the Chief Signal Officer 
for 1865, Cheyenne, in Wyoming Territory, at an elevation of 
about 6000 feet, has an annual mean temperature of 43°.6 ; Den- AND ITS RELATION TO PULMONARY DISEASES. 
5 
ver, at 5200 feet elevation, 49°.2 ; Colorado Springs, at 6000 feet, 
46°.8; Sante Fe, New Mexico, at 6800, 49°.2 The last is the 
same as the annual mean of Denver, while the difference in alti- 
tude between Denver and Santa Fe, 1500 feet, is about equiva- 
lent to five degrees of temperature; the difference between the 
same four degrees of latitude on the Atlantic coast being ten 
degrees, according to Prof. Henry’s Temperature Chart of the 
United States. Generally speaking, the average temperatures of 
different localities in this region are a few degrees lower than 
those of places of the same latitude on the Atlantic coast, yet 
not nearly as much lower as might be expected, judging by the 
rule of one degree lower temperature for each 300 feet rise in eleva- 
tion. Besides, the abundance and intensity of the sunshine, fur- 
nishing diurnal radiation, give the impression to all of a rela- 
tively higher temperature than the records show, which are 
taken in the shade. 
In getting the mean daily temperature in winter, the night ob- 
servations, when people are mostly indoors, affect the very favora- 
ble day observations, when being outdoors is chiefly attractive.1 
*The dryness and rarity of the air are generally felt to lessen the 
severity of sudden changes or extremes. 
So, as to temperature, this climate compares quite favorably 
with eastern places of the same latitude, especially for those per- 
sons who are much out of doors, and subjected, in an atmosphere 
of remarkable diathermancy, to the direct rays of the sun. 
Rain-fall and Relative Humidity. 
The annual rain-fall varies from eight to twenty inches, the 
least fall being in the valleys, and the greatest on the Divide and 
foothills. From October to April this moisture generally comes 
in the form of a light snow, which melts as it falls or soon after. 
There is not much regularity in the storms of this section, ex- 
cept the daily afternoon showers in July, or about that season, 
while storms are quite infrequent during the fall and winter 
months. 
The low ratio of relative humidity is remarkable, while the 
absolute humidity is still less than the relative. For, as the capa- 
1 The 9 P. M. record is doubled to get the average temperature according to the 
rules governing the Signal Service Bureau; 6 
REPORT ON THE CLIMATE OF COLORADO, 
city of air to hold moisture is governed by its temperature which 
is changed by rarefaction, and as the pressure to the square inch 
is a fifth less at an elevation of 6000 feet than at sea-level, there- 
fore air at the foot of the mountains has less absolute moisture than 
at sea-level. But the air seldom reaches saturation here, and 
sometimes during long storms from upper strata of clouds, the 
degree of saturation is between seventy and eighty per cent., the 
annual average being about forty-six. This condition, the di- 
athermancy of the air, and increased radiation of heat acquired 
directly from the sun, favor rapid evaporation and diffusion of 
moisture. This is exemplified by the fact that the signal service 
observer has to fill the cup of his wet bulb thermometer twice a 
day at Denver, while at some stations east it is done but once in 
two days. According to records kept by these observers at Den- 
ver for ’73, ’74, and ’75, there have been but eleven days in that 
time during which the sun has been wholly obscured by clouds. 
There are no regular fogs or night dews here. The dew point, 
around which the temperature at night hovers, and is controlled 
in moister climes, is almost never reached, the colder tempera- 
ture at night being attributable not to evaporation, but the with- 
drawal of the sun’s influence. 
With these facts in view, I think I am warranted in saying 
that the 46 per cent. “ relative humidity,” the mean for a year in 
Denver, indicates not half the absolute moisture existing on the 
Atlantic and Pacific coasts, and in the valleys of eastern rivers, 
where the mean relative humidity reaches 70 to 80 per cent. 
This section of Colorado is probably dry enough for comfort, 
whether a still smaller ratio of moisture would be preferable for 
some invalids remains to be proven, in view of special classes of 
cases to be treated. 
Winds. 
The mountains to the west undoubtedly have a salutary influ- 
ence on this climate, especially as affecting the character of the 
winds. This is shown by the signal service charts, giving the 
wind directions which are most and least likely to be followed by 
rain. 
In the following table I have averaged these records for the 
whole year for stations in this vicinity. AND ITS RELATION TO PULMONARY DISEASES. 
7 
Winds most likely to be 
followed by rain. 
Winds least likely to be 
followed by rain. 
Cheyenne, N. E. E. S. E. S. S. W. W. 
Denver, N. N. E. E. S. S. W. W. 
Pike’s Peak, S. S. W. W. N. N. E. E. 
Same Fe, S. E. S. S. W. N. W. N. N. E. 
This table is very significant, for it will be observed that the 
winds, viz., the south, southwest, and west, which bring storms 
on Pike’s Peak, are the very ones which harbinger pleasant 
weather for Denver, Cheyenne, and northwestern Colorado. The 
mountains have acted as condensers and deprived them of their 
moisture. It is not an unfrequent occurrence to see storm clouds 
hovering around the lofty mountain peaks to the west, or as it 
were ineffectually endeavoring to spread out toward the east, 
while quiet and sunshine rule over the plains below, the storm 
being held by the mountains or opposed by eastern currents. 
Then again the moist winds from the Grulf of Mexico condensed 
as they are cooled by rising, and as they meet the Rocky Moun- 
tain range, give up their moisture in eastern New Mexico, are 
turned to the north, and come to us bringing pleasant weather. 
The north returns the compliments of the south, for the north, 
northeast, and east winds, coming up from the valley of the Mis- 
souri River, bring most of the storms for northeastern Colorado, 
and thus sweated of their rain push on to Mexico, or rising above 
the southern current, give their moisture to the plains, and pleas- 
ant weather to the southwestern mountains. 
The winds of Colorado are fitful, and if rapid are on the plains 
of short duration. It is to be remarked that the force of winds, 
the rapidity being the same, is much lessened by reason of the 
lightness of the air. Sometimes preceding a storm, or accom- 
panying some atmospheric disturbance, the wind swoops down 
as it were from aloft, or comes in a cloud of dust and sand, espe- 
cially when the hard-baked soil is loosened by travel. These 
dust storms give an unfavorable impression of the climate. The 
inconsiderable force and the infrequency of these marked disturb- 
ances may be inferred from a table of winds in the annual report 
of the Chief Signal officer, which gives us interesting statistics, 
showing the infrequency of winds in general. Take the winds 
of winter : since for the rest of the year they are noticed as blow- 
ing quite evenlj’’ as to direction, except the south wind, which 
generally blows more frequently than the others, and the north 8 
REPORT ON THE CLIMATE OF COLORADO, 
wind in spring and autumn twice as often in Colorado Springs as 
in Denver. Of the eighty-one signal stations where the full 270 
observations (i. e. three daily) were reported for the winter of 
1874, the observations denominated “calm” were 58 at Denver 
and 71 at Colorado Springs; the latter being the seventh, and 
the former the ninth highest. At only two stations, Burlington, 
Vt., and Portland, Oregon, were the south wind observations in 
excess of those at Denver, namely 7b out of the 270. As these 
south winds are usually soft breezes from the Gulf of Mexico, 
deflected to the north and passing under the high belt of west 
winds, which come over the Rocky Mountains, a large propor- 
tion of pleasant weather is thereby explained. 
Cheyenne, just over Colorado's northern border, is less pro- 
tected by the Rocky Mountains than points south, since nearly 
half of the winter winds are recorded as from the west. But 
Cheyenne was more favorably circumstanced as to the infre- 
quency of the disagreeable north, northeast, and northwest winds 
than any place except Virginia City, Montana, while Denver had 
less of these winds than 66 out of the 81 stations. As to the total 
amount of wind on the plains, there is an interesting chart in the 
statistical atlas of the last census of the United States, which gives, 
in a pictorial way, “the total movements of the air with resultants” 
for the year ending with May, 1878. There are sixty-two signal 
service stations represented in this chart, including three in this 
vicinity, i. e., Cheyenne, Denver, and Santa Fe. Reckoning in 
order, from the least to the greatest total movement of air at all 
these stations, Denver is found to be about the tenth, Santa Fe 
the sixteenth, and Cheyenne the forty-sixth. 
It can be concluded, then, that along the eastern base of the 
Rocky Mountains it is not very windy, either as to the number 
of winds observed, or t-he total movement of the air, those winds 
generally prevailing which bring pleasant weather. 
Atmospheric Electricity. 
The climate of this elevated region is pre-eminently stimulating. 
That this quality is chiefly due to the increased amount of at- 
mospheric electricity I have no doubt. As we rise in altitude 
the electric dose increases, and some organizations are percepti- 
bly influenced thereby; some to their injury and others with AND ITS RELATION TO PULMONARY DISEASES. 
9 
apparent benefit, so far as their feelings are concerned. The 
medicinal effects of this element which surrounds us is a subject 
which, while extremely fascinating and giving promise of valu- 
able information in return for labors devoted to it, is fraught 
with many difficulties, because of the very nature of the element 
itself. 
Scientists tell us that the “atmosphere always contains free 
electricity, which is almost invariably positive.” Alexander 
Buchan says that of 10,500 observations at Kew Observatory, 
10,17(3 were positive and 3(31 negative. When the sky is cloud- 
less the electricity is positive, the intensity increasing with the 
height. Among other experiments, that of Becquerel and Bres- 
chet of shooting an arrow, attached by a delicate conductor to 
an electrometer, vertically into the air, proved conclusively the 
increased electric tension at a height of 250 feet. If even a less 
proportionate increase exists for altitudes of four to eight thou- 
sand feet, then the large amount of atmospheric electricity at the 
base of the Rocky Mountains is explained. Instances of parties 
receiving shocks when passing over eminences in the mountains 
are not uncommon, and of force enough to cause a lengthened 
disturbance of the equanimity of the nervous system; as one 
explorer said to me, “to make one’s hair stand on end.” 
Whether the electricity of high altitudes exists in an inverse 
ratio to that of oxygen, and whether or not we breathe electricity 
as we do oxygen, as suggested bv the late venerable Dr. George 
O. Jarvis, of Portland, Conn., are intricate questions which are 
yet to be solved, when science teaches more of this subtle agent 
than at present. 
But if we do breathe atmospheric electricity, then aside from 
the increase due to this altitude, we inhale a fifth more of it at 
about 6000 feet elevation than we would at sea level, to get the 
same amount of oxygen. This is based on the fact that there is 
a difference of one-fifth in weight in a specified volume of air, 
which is due to the difference between sea level and the altitude 
of 6000 feet. Whether living on this atmospheric stimulant we 
have to take less in weight of oxygen to get along in life is 
another intricate question which I have not space here to discuss, 
even if I were able. 10 
REPORT ON THE CLIMATE OF COLORADO, 
Ozone. 
Our surmises1 as to the existence of a large proportion of 
ozone in this region are destined to be verified. The almost 
total absence of swampy land, and the small amount of decaying 
or putrefying material to use up ozone, would explain an ex- 
pected excess on most of the Rocky Mountain slope. 
My observations in the centre of Denver last winter were 
uncertain and unreliable till, by the aid of Prof. Kedzie, of 
Michigan, I learned that the sulphurous fumes from the soft coal 
we burn neutralized this agent. I am further of the opinion 
that the extreme dryness of the air in Colorado in a measure 
vitiates the results of Schonbein’s starch and iodide of potassium 
test used.2 
The Seasons. 
While the variations of temperature from summer to winter, 
probably also of atmospheric electricity and ozone, considerably 
influence the effect of this climate on pulmonary diseases, espe- 
cially as increasing the effect of altitude in cold weather, yet 
for many of these invalids our winter climate is paradisaical 
compared with that of cities and towns along the northern lakes 
and rivers above Mason and Dixon’s line, with their chilling 
winds and saturated atmosphere. 
As the growing idea becomes more universal of a stimulating 
and tonic climate for those chronic lung diseases of which there 
is any hope, Colorado will be better known as a winter home for 
invalids. 
While exceptional storms and cold snaps must be expected, 
the average winter of Colorado is a blessing, inviting to almost 
daily rides and walks all those who are able to be out of doors, and 
no others (asthmatics excepted) should be urged to come to Colo- 
1 “ The Influence of the Climate of Colorado on the Nervous System,” Archives 
of Electrology and Neurology for November, 1874. 
2 Since then a sufficient number of careful observations have been taken by 
friends in the suburbs of Denver, on the Divide, and in the mountains, to show 
that the records of ozone in Colorado will compare favorably with those, the only 
ones I have for comparison, taken at the Agricultural College of Michigan by 
Prof. R. C. Kedzie, and at St. Paul, Minn., by the signal service observer, J. A. 
Bar wick, now of the Denver Signal Station. 11 
AND ITS RELATION TO PULMONARY DISEASES. 
rado, as indoor life has no special advantages. The winter which 
has just passed has surpassed my expectations in this life in con- 
tinuous genial sunny days and absence of disturbing elements. 
Winter weather is quite as likely to come in spring as before 
it. But between occasional snow and dust storms, sample Colo- 
rado weather is sandwiched all through spring. In summer the 
days are warm, though somewhat relieved by the July showers 
and gentle breezes, while the nights are generally refreshingly 
cool. 
In summer and early autumn the mountains are enticing to 
almost every one, for a more exhilarating and delightful atmos- 
phere than the plains afford. I think autumn is the best, the 
most evenly sunny season of them all. 
Scenery. 
A long report could be written on the scenery of Colorado 
alone. Aside from a lack of space, I must confess myself unable 
to do the subject justice at the present time. It is noteworthy, 
however, that the Pocky Mountains with their parks and canons 
offer valuable adjuncts to Colorado’s treasures of climate; en- 
ticing the invalid tourist to restorative hardships which, without 
these pleasurable incentives, would never be undertaken. That 
the mind can forget the bodily ills, with which it has long been 
harassed, is a blessing which comes with the rapture and sub- 
limity excited bj' Nature’s wonders in Colorado. Such are the 
“ Grand Canon of the Arkansas;” “The Garden of the Gods ;” 
the rugged gorges through the mountains; the lofty mountain 
peaks towering like “ Ossa on Pelion piled” above the lesser 
heights, giving variegated and extensive views of the surrounding 
country ; the ever-varying grandeur of the foothills, mountains 
and snow-capped peaks as seen from the plains, now shaded by 
clouds, tinted with snow, or differently changed by the seasons; 
the beautiful sunsets, which in autumn reach a climax of magnifi- 
cence long to be remembered by the fortunate beholder. 
Pulmonary Diseases. 
As an apology for devoting so much space to the description 
of Colorado’s climate, I wish to aver that the subject covers too 
much ground to be minutely and comprehensively treated in a 12 
REPORT ON THE CLIMATE OF COLORADO, 
report of this character. This will explain the absence of many 
illustrations, and explanatory tables which would make the re- 
port plainer to all. 
But a somewhat extended description of the climate is neces- 
sary. For if physicians are to take the responsibility of sending 
their patients to the Eastern Rocky Mountain Slope, they will 
for the most part reason the matter out themselves, knowing the 
basis of benefits to be expected. So if any differ with me as to 
the following conclusions, they have the preceding data, which 
they can rely upon in deciding whether to recommend their pa- 
tients to journey to Colorado. 
The clinical results are such as might be expected under these 
existing conditions, and the organs of respiration are those 
chiefly influenced. 
The therapeutic efficacy of this rarefied atmosphere in lung 
diseases, springs from a healthy respiratory activity which is 
opposed to the theory of rest, the paramount idea in the treat- 
ment of many other ills. This may be regarded as respiratory 
gymnastics, its gauge being the lessened atmospheric pressure, 
which is about twelve pounds to the square inch at 6000 feet 
above the sea. I will briefly illustrate this effect as it varies in 
different pulmonary diseases, commencing with that one which 
is most decidedly benefited. 
Asthma. 
Of all the remedies which have been recommended in the 
treatment of this troublesome malady, I know of none which 
can compare with the light air of this inland region. I speak 
thus highly of our prescription, feeling that, almost without ex- 
ception, uncomplicated cases of asthma may gain decided relief 
or a permanent cure in Colorado. And, as to complications, the 
relief of the asthma often more than counterbalances the unfa- 
vorable effects of elevation in cardiac lesions, cavities in phthisis, 
and marked emphysema.1 
The mistaking emphysema for asthma, and the advanced age 
1 An asthmatic patient I have in mind, with enlargement of the heart, mainly 
from dilatation of the left ventricde, with aortic insufficiency, has twice by advice, 
on account of the heart disease, gone down from this elevation, but with such 
poor relief of his general symptoms, that he was contented to return to remain in 
Denver. AND ITS RELATION TO PULMONARY DISEASES. 
13 
of some wlio have had asthma many }7ears, with perhaps the lung 
tissue seriously involved, will sometimes, I think, explain the 
only slight benefit received. Generally speaking, the relief is 
marked as the base of the mountains is reached, and often after 
crossing the Missouri River. If all the results were written, hun- 
dreds of the present residents of Colorado could be cited who 
had asthma months or years before coming here, who had ex- 
hausted all the other known means of relief in vain, but who 
have now been nearly or quite free from asthmatic symptoms 
since becoming residents of Colorado. 
I will mention only two or three instances by way of illustra- 
tion. A lady from Vermont, of marked nervous temperament, 
perhaps from long suffering; twenty-four years old and an asth- 
matic since childhood; had tried almost every means of relief. 
From the age of fourteen, till she came to Colorado nearly a year 
ago, she had been but three or four days in each month free 
from asthma, the exacerbations of the paroxysms being coin- 
cident with the catamenia. After marriage she was advised 
to bear children with hopes of relief; but two months after 
becoming enceinte, the asthma had so greatly increased that she 
“ had to come to Colorado.” Since then she has been almost 
entirely free from dyspnoea, she is the picture of health, and happy 
to make her future home under the shadow of the Rocky Moun- 
tains. 
Mr. F. J. B. Crane, of Denver, who has shown much interest 
in his fellow sufferers, was chairman of a committee, represent- 
ing a convention of asthmatics held in 1878. They collected 
the histories of 120, some of them exceedingly obstinate cases;, 
all of whom were evidently cured or much relieved in Colorado. 
Mr. Crane was from Detroit, Michigan. “Had asthma for more 
than thirty years, and badly for fifteen ; for over ten years had 
been disturbed every night; travelled in most of the United 
States and abroad without benefit; arrived in Denver in March, 
1871; after three weeks, was surprised one morning to find he 
had slept all night;” this he did every night after that while he 
remained ; went to Detroit, the disease returning after a short 
time, and that winter he suffered more than ever before; returned 
to Colorado in April, 1872, and the asthma left him after two 
weeks and did not trouble him again until the next year, when 
again going east for a short visit, he was attacked with dyspnoea 
while crossing the Missouri River at Omaha. 14 
REPORT OX THE CLIMATE OF COLORADO, 
The plains at the foot of the mountains are not high enough 
for some asthmatics, who may find relief by going to the Divide 
or some of the mountain towns. A permanent residence here is 
in most cases necessary. 
What is the rationale of this marked effect? 
While the increased amount of atmospheric electricity, the 
dryness and purity of the air may be important auxiliaries, I am 
of the opinion that it is due to the mechanical influence of lessened 
atmospheric pressure. The modus operandi seems to be as follows : 
Asthma being defined a paroxysmal contraction of the circular 
muscular fibres of the smaller bronchial tubes; the muscles con- 
cerned in expiration are in a condition for normal activity when 
the thorax is distended, while the muscles producing inspiration 
seem to be more intimately associated than the others with the 
constricted fibres of the bronchial tubes. Inspiration then, as 
compared with expiration, is especially difficult because of this 
constriction. Now lessen the density of the air breathed, and 
the lungs must labor with more air to get the same amount of 
oxygen as before, sufficient to sustain life. The increased respi- 
ratory labor, compressing the air, gives a proportionately greater 
pressure on the inside of the lungs than before, compared with 
that of the surrounding atmosphere. 
Thus augmented within, outward force distends the constricted 
circular muscles of the bronchial tubes to a point where they 
lose their spasm. Their contraction is simply no longer possible ; 
as with the hand we can lift a ball which the fingers can grasp, 
but if the ball is simply increased in size, a point is reached 
when the fingers lose their power and it is dropped. In such a 
way, I conceive, the expansion of the smaller bronchi is produced 
by the outward pressure of the air within them. A lady, an 
asthmatic from Pennsylvania, while climbing the mountains with 
some friends, was so troubled with dyspnoea that, coming to a 
large rock, she declared (woman-like) she could never reach the 
top. In response to the urging of her friends she made the effort, 
expecting to await their return on the top of the rock. But after 
a short rest she found the difficulty of breathing had gone, and 
she ran with ease to catch up with them. What was it which 
so suddenly opened the bronchial passages to the free admission 
of air, if not this mechanical effect of the rarefied atmosphere? AND ITS RELATION TO PULMONARY DISEASES. 
15 
Emphysema. 
I hardly know what to say about emphysema, so few uncom- 
plicated cases come to Colorado. I closely watched a patient in 
one case, and was surprised at his improvement, but his lungs 
were otherwise defective, and he came from the miserable climate 
of Chicago. The emphysema may have been secondary to a 
broncho-pneumonia, which the climate here benefited. I believe 
simple emphysema will be aggravated by this and higher eleva- 
tions. 
Prevention of Phthisis. 
I need only refer the discriminating mind to the first part of 
this report for evidence that there is prolongation of life, health, 
and happiness in Colorado, for thousands of those who are des- 
tined by inheritance or acquired tendency to die of consumption 
where they now live. The increased respiratory power, due to 
elevation, is accompanied with improved alimentation and capil- 
lary circulation. More perfect elimination follows improved 
digestion, and life, while it may be more rapid, becomes more 
perfect for all who have taints of constitution to battle with. Espe- 
cially for the young with tubercular and scrofulous tendencies, 
is an active outdoor life on the plains to be recommended. 
Bronchitis. 
Acute bronchitis is not especially frequent or severe. One is 
not very likely to take “cold” in an atmosphere as uniformly 
dry as this. Yet, sometimes during cold weather there is liable to 
be a short season, when influenza and “colds” are quite general. 
Capillary bronchitis, especially in children, is, I believe, ag- 
gravated by high altitudes. This would be expected from the 
increased labor required of the lungs. 
I hardly know what to write of chronic bronchitis, having 
become suspicious from often finding it simply a symptom of 
further lung trouble, which had before attracted but little atten- 
tion. It is much like the “catarrh” which in the States is prone 
to attach itself to failing constitutions. Such bronchial catarrhal 
conditions, or rather the depreciated states which give rise to 
them, are most favorably influenced by an outdoor life in this 
sunny climate. 16 
REPORT ON THE CLIMATE OF COLORADO, 
Pleurisy. 
Pleurisy, associated with cough, as would be expected, is hard 
to bear. It is chiefly met with in those whose lungs are defective, 
and not often as uncomplicated. Where one is deprived of the 
use of a considerable portion of lung surface, and the pleura 
covering another portion is affected, his condition is especially 
unfortunate in very high altitudes. 
Pneumonia. 
Acute uncomplicated pneumonia is not often met with com- 
pared with its frequency in damp climates.1 But when it does 
occur, excluding some very mild cases, the influence of elevation 
is of an aggravating character. Unlike a slow chronic pneu- 
monia, the lung needs rest, which it cannot have. The fatality of 
double pneumonia is especially to be feared. Pneumonia is to he 
dreaded in little children, in whom the fever is apt soon to run high. 
What is done for them must be well directed and immediate, for 
the reward of efficient treatment is often as surprising to the 
physician as the intensity of the fever. This is one of the in- 
stances where the disciple of a limited sect is wont to show his 
good sense in treatment by the degree to which he abandons the 
precepts of his pathy. 
In claiming infrequency of pneumonia, exception must be made 
of a peculiar phase of the disease, which sometimes is almost 
epidemic in winter at great elevations. 
This high altitude pneumonia shows its special and severe 
character, as it attacks miners who remain high up in the moun- 
tains all winter, as on Mounts Bross and Lincoln, where mines 
are continuously worked between 12,000 and nearly 14,000 feet 
above sea level; at these places some of the strongest men are 
taken, first with a chill—generally on coming out of the mine 
after a day’s work, followed by great pain in the chest, expecto- 
ration of blood, and sometimes extensive hemorrhage; a dry ery- 
thematous condition of the mucous membrane lining the nasal 
passages, fauces, and bronchi is noted. The symptoms of pulmo- 
nary congestion rapidly supervene, and are very decided in the 
fatal cases, which seem to be in a ratio corresponding to the alti- 
1 See mortality statistics in U. S. census 1870. AND ITS RELATION TO PULMONARY DISEASES. 
17 
tude. Improvement is generally noticed on descending to the 
valley. I cannot say much of the treatment, having had little 
experience with typical cases in Denver. I saw one case, ap- 
parently of this character, in a robust, middle-aged man, with my 
friend Dr. Stedman. We bled him freely, at first with marked 
relief of the great constriction and pain in the chest, followed by 
rapid resolution and recovery. 
Pulmonary Hemorrhage. 
While hemorrhage is mainly to be considered as a symptom of 
commencing or seated pulmonary disease, it is well to examine 
what influence elevation has in the premises. Is it a frequent 
occurrence in Colorado? Exempting cases of phthisis with ex- 
cavation in the lungs, the high altitude pneumonia already men- 
tioned, and making some allowance for the large number of the 
inhabitants who have come to Colorado, because of pulmonary 
disease, and pulmonary hemorrhage is rare. It seems that the 
healthful condition of circulation, and atmospheric pressure 
within the lungs, acts as a preventive in some cases by relieving 
the hyperasmia which precedes hemorrhage. At the same time 
it is plain that when pulmonary hemorrhage does occur, much 
elevation, by the increased demand on respiratory organs, would 
somewhat seriously complicate matters. So it is with the hemor- 
rhage which comes from a cavity in the lungs. The stretching 
which this part gets is anything but remedial. 
As to the hemorrhagic cases of phthisis, they are here as else- 
where the most favorable. 
While I have known of invalids bleeding at Omaha and on 
the way to Colorado, and after their arrival being free from it, 
yet I believe the precaution is a good one, to avoid a sudden and 
great rise in elevation, after a recent pulmonary hemorrhage, 
especially if there is a local injury or cavity in the lungs. 
A sojourn of a week at some midway station (as at Wallace, 
on the Kansas Pacific Kailway), is advisable for some of these 
invalids, or, better still, if in summer, a ride across the plains in 
a wagon, and camping out on the way. 18 
REPORT ON THE CLIMATE OF COLORADO, 
Chronic, “ Uncured,” Catarrhal, Croupous, and 
Desquamatial Pneumonia. 
Reserving for a future occasion the report of my cases of 
phthisis, I will briefly state here a few points in reference to the 
disease. The various forms of pulmonary defects (chiefly inflam- 
matory) which the profession are coming to consider as consti- 
tuting the first stage of consumption, are particularly referred to 
under the above heading. This may be the place, but there is 
not now the time nor space, to fully discuss the differential diag- 
noses of the pathological states referred to. Of course, in the 
present transitory stage of professional opinion on this subject, 
there may be some confusion, and misconception of terms used ; 
but speaking now only in a general way, I hope to make myself 
understood. 
The character of diseases referred to are of a chronic tendency, 
affecting mainly the apices of the lungs, chiefly known by the 
local physical signs of lessened expansion, dulness, bronchial or 
difficult respiration, prolonged expiration, exaggerated whisper, 
vocal fremitus, and resonance. 
Now, excluding these cases, after breaking down of lung tissue 
has commenced, also those complicated with heart disease, in- 
tense fever or a very rapid pulse, and I can speak almost as 
favorably of the curative effects of the climate of Colorado in 
these conditions as in asthma. They are almost as certainly 
benefited. It is strange that infiltrated substance and hypertro- 
phied tissue become absorbed, and peripheral portions of lung, 
which were before useless, become opened again to the healthful 
admission of air. Yet this occurrence is verified in the experi- 
ence of many residents of Colorado, however poor our explana- 
tion of the modus operandi may be. If the foregoing account of 
the effect of lessened atmospheric pressure in asthma is correct, 
then the same influence has great weight in the pathological 
conditions here cited. The apices and peripheral portions of the 
lungs are the special seats of this early inflammation, the hyper- 
trophied condition of epithelium, and infiltration with epithelial 
debris which results. 
In ordinary life, and especially in indoor sedentary occupations, 
the apices are the least used and most abused parts of the lungs. 
Prof. Hutchinson, in his late clinical lecture on “The Inflam- 19 
AND ITS RELATION TO PULMONARY DISEASES. 
matory Origin of Phthisis,” has so excellently described the 
mechanical effects, “the disparity in power,” in the apices of the 
lungs, leading to inflammation of the air cells in consequence of 
the impaction of epithelial debris, and especially aggravated in 
enfeebled conditions (“the paralytic thorax” of the Germans) by 
the act of coughing, that I wonder he did not think of the 
mechanical agent nature furnishes in Colorado’s elevated climate, 
to hasten absorption and a return of the enfeebled lung tissue to 
a heathful condition. It is noticeable that authors of standard 
works have heretofore generally slighted this common sense 
means of treating the difficulties under consideration. The res- 
pirations with increased altitude are at first faster and then deeper. 
The circulation, with improved alimentation, responds quickly 
in consonance with the increased respiratory activity. While 
the quicker life inaugurated carries with it a more perfect condi- 
tion of waste and repair of tissue all over the body, the capillary 
circulation in the lungs is becoming less impeded, because the 
greater quantity of dry air inspired is gently crowding before it 
the obstructing secretion, epithelial debris, and hypertrophied 
tissue, which clog the alveoli and smaller bronchi. It is thus, I 
conceive, the maximum respiratory capacity is again restored in 
lungs which were starting on the road to destruction. 
The unfavorable influence of scrofulous tendency, heredity, 
old age, lack of energy to get well, etc., must be noted in count- 
ing on the certainty or uncertainty of benefit from climate, as 
well as from any other means. But if the patient has the ivill 
to fight his enemy at every point, under the advice of those who 
are able to serve him, he may be almost sure of great benefit by 
a continuously active outdoor life in a higher and lighter atmos- 
phere, with the other advantages the eastern Rocky Mountain 
slope affords. 
Cheesy Pneumonia and Pulmonary Tuberculosis. 
Continuing to speak in a general way, we come to more serious 
conditions, with which the elements of uncertainty and experi- 
ment, so far as climate is concerned, have more to do than with 
those just considered. 
These seated diseases of the lungs furnish less favorable prog- 
noses everywhere. 
The evidence upon which we can speak with much needed cer- 20 
REPORT ON THE CLIMATE OF COLORADO, 
tainty, must come from carefully recorded statistics of a good 
number of typical cases. Such results I hope to be able to pre- 
sent at no far distant day. 
It is now important to note that these conditions, when in- 
cipient, may be considered in nearly the same light as those 
which precede them in this report. 
As the pathological states under consideration progress, com- 
plications are liable to be met which will lessen the chances of 
recovery or permanent relief. But with the exceptions already 
noted, the climate of Colorado, with the right kind of outdoor 
life, is full of promise in these conditions all the way up (down ?) 
to the stage of “softening.” When this breaking down of lung- 
tissue has commenced, I do not wish to take the responsibility of 
indiscriminately recommending the climate of the Rocky Moun- 
tain region. 
After this unfortunate stage many could live more comfortably 
and even longer at their homes surrounded by friends, or in other 
climates than those of great elevation. 
A cavity surrounded by diseased lung-tissue inclining to cheesy 
degeneration or thickly studded with tubercles, may be the cause 
of a rapid decline, when a high altitude is quickly reached, 
because of the sudden breaking down of this diseased tissue next 
to the cavity. Some may agree with me in preferring to run the 
risk of being rid of this diseased tissue, but there are milder ways 
to be chosen of “letting down” these unfortunates, who are so 
near death any way. 
If physicians do take the responsibility of sending patients 
with cavities to Colorado, the other circumstances and conditions 
should be favorable, and if possible a slow rise in elevation 
(preferably in the warm months by teams across the plains) is to 
be recommended. For such there is encouragement in this fact, 
that many similar cases have come here, who have steadily im- 
proved, or seemed to have their lives very much prolonged. 
It is to be noted here that having once gained relief in Colo- 
rado of serious lung disease, a return to one’s old residence in the 
lowlands is a dangerous experiment unless for a short stay dur- 
ing a favorable season. The truth of this could be shown by 
many sad examples. 
A prolonged or permanent residence is to be recommended. It 
is also to be noted, that the responsibility is great which rests AND ITS RELATION TO PULMONARY DISEASES. 
21 
upon physicians of making an early diagnosis of the conditions 
which should send their patients to Colorado. 
Physicians by the sea may say that the lessened atmospheric 
pressure gives us in Colorado an advantage, in making a physi- 
cal examination of the lungs, by the more marked contrast 
afforded between dulness and resonance, the evidence of vomicae 
which were before concealed, etc. Nevertheless the responsi- 
bility rests mainly with the family physician of deciding at an 
early date whether or not his patient needs the change. Certain 
it is, .most of the phthisical patients who have come to Colorado 
(with some exceptions, notably, to my knowledge, those coming 
from a few Chicago physicians) have not removed to this climate 
as soon as they might with much increased benefit. If physicians 
will generally come to discriminate more carefully as to when and 
where their patients shall seek the benefits of climate, then there 
is no doubt that the once barren plains east of the Rocky Moun- 
tains will soon “blossom as the rose,” teeming with the renewed 
life which the dry, sunny and rarefied atmosphere affords.