1762 REPORT OF THE CHIEF OF ENGINEERS. 



The average temperature is about that of New York and Philadelphia, hut heat 

 and cold are not so perceptible, since the hot nights experienced in the East are un- 

 known here, and on account of the excessive dryness of the air there follow many 

 bright and lovely days. The latter fact is attested by any one's experience, and the 

 •meteorological records of Denver show that during three years there were hut twelve 

 days during which the sun was totally obscured by clouds. The former is a well- 

 known fact, a temperature of 10° above zero in New York Harbor being far more severe 

 upon the system than that of 10° below in the mountains. With the moist atmosphere 

 of the seashore a similar degree of cold would in the mountains be unbearable. No 

 matter how warm it be in the sun, a breeze or current of air will always be felt in the 

 shade. The diurnal variation of the temperature is considerable, and increases with 

 the altitude. With an increase in rarefaction corresponding to the elevation, the heat ' 

 of the sun passes more readily through the atmosphere, and upon the highest mount- 

 ains the midday heat is burning ; with the setting of the sun the atmosphere as readily 

 gives forth its warmth and an opposite temperature succeeds. Within a valley of 8,500 

 feet elevation in August, traveling at noonday Avas almost intolerable, while during 

 the night water was frozen in buckets near our tents. 



The air being at the bases of the mountains, say, one-fifth lighter than at the sea- 

 coast, there would be a square inch pressure of 12 pounds instead of 15 as at the sea- 

 shore, whence would result the extra exertion of the respiratory organs to the extent 

 of one-fifth to obtain the requisite amount of oxygen. 



With increased altitude is associated also greater amounts of electricity. At lofty 

 elevations electric phenomena are often more marked than pleasant. In snow-storms 

 upon mountain tops we have witnessed the strongest and most disagreeable manifesta- 

 tions thereof, with peals of thunder accompanying, to the delight of neither man nor 

 mule. 



The increased respiration necessitated, resulting soon in greater chest development, 

 the stimulated nervous system, the increased blood circulation, with diminished atmos- 

 pheric pressure, all combined with the electrical influences of a tonic nature, have 

 directly resulting effects in a more salutary condition of existence. 



The diseases for which this climate should be sought are asthma, chronic bronchitis, 

 and incipient phthisis pulmonalis. By invalids suffering chiefly from troubles allied 

 to the many stages and forms of pulmonary consumption this region will be always 

 sought. All such as go in time will be benefited; with proper care and treatment, and 

 the mode of life adapted to their cases, they will recover. Those going too late, will 

 have their disease assume advanced forms sooner than elsewhere, and the later stages 

 and death will sooner occur. 



The number of consumptives who have sought relief in Minnesota and Florida is 

 very great, readily understood from the statement by high medical authority that 

 over 20 per cent, of deaths in the East from all causes are from this malady. 



The railroad companies have extensively advertised the climate of Colorado as a 

 sure specific for this disease, and many in stages far advanced are lured from homes 

 and fond ones only to find an earlier grave. But to those who go in time, not hope- 

 lessly yielding to the malady, not content to remain in first-class hotels and boarding- 

 houses, but determined to lead an outdoor life, with the fascinations of " camping 

 out" amid magnificent scenery and the sports and pleasures to be found therein, to 

 them will come a new lease of life. 



In order, however, to arrive at these gratifying effects, various degrees of altitude 

 should be essayed by the invalid, as their adaptation varies with the case and its con- 

 dition. Those with weakest lungs and suffering from hemorrhage should avoid great 

 elevations. 



In the older time, before the railroad spanned the plains and the journey from the 

 Missouri River necessitated a month or more, invalids became acclimated as they 

 traveled slowly up the great plateau to the mountains, and when the base was reached, 

 a cure had almost been effected. The rapid transit of the present day is to the detri- 

 ment of the invalid. If the elevation does not bring improvement, the patient should 

 try one of less altitude and ascend later ; an exercise of good j udgment will soon de- 

 termine what point is best suited to his case, when an outdoor life should be fol- 

 lowed. 



There are a number of diseases, chiefly of chronic nature, upon which the effects of 

 high altitudes are not yet positively known and for which they should, therefore, not be 

 sought. Such are chronic rheumatism, neuralgia, chronic catarrh, and the periodical 

 malady known as u hay-fever." The remedial effect of some of the hot sulphur springs 

 of the State in rheumatic troubles of long standing is yet to be definitely determined. 



Other diseases exist to which these great altitudes are highly aggravating, chiefly epi- 

 lepsy, chorea, and all forms of cardiac disease. To those so afflicted approach to lofty 

 elevations should never be made, as in many instances fatal results have ensued. 



To those camping out in the open air, slight inconvenience is at first found in the 

 effects of the dryness of the atmosphere and the hot rays of the sun. The skin, when 

 exposed, on hands and face, peels off in the most annoying manner and soreness ensues, 



