Rocky Mountain passes in this State Argentine is the has many climates at once. At midsummer the highest, being 13,000 feet above the sea, and can be plains and foot-hills sometimes become heated and used only in the summer. There are five others above uncomfortable; but the higher mountain towns have 12,000 feet high, and seven below 10,000 feet. a very agreeable summer climate. The foot-hill country has a mild winter climate, the snow never becoming very deep and seldom lying long. Sharp thermal changes are common, but they do not so readily affect the sensations as in lower and moister regions.

As the climatology of Denver, situate 5197 ft. above sea-level, fairly represents that of both the plains and the foot-hill country, we append its weather record. By this the mean monthly_temperature February, 35°; March, 36°; April, 49°; May, 61° June, 64°; July, 74°; August, 71°; September, 63° October, 51°; November, 38°; December, 28°; the highest temperature, during this period, 98°, having been reached in the month of July-lowest, 20° below zero, occurring in the month of January; annual average of precipitation, snow and rain, 15 in. of water. There occurred during this time a yearly average of 162 clear days; 135 that were fair or partly clear; 15 that were cloudy but not stormy, and 53 that were more or less stormy, there having been but few entirely stormy days in any year. Not very often, in fact, do either snow or rain fall here continuously for 24 hours. The season of snow-falls reaches from November till March, the most of the rain falling during the later spring and the summer months, and occurring in the form of showers. The line of perpetual snow ranges between 12,000 and 13,000 ft., although in some places, as on the northerly slopes of the mountains and where it drifts into deep cañons, it lies throughout the summer much lower down. It is one of the thermal peculiarities of this region that a strong west wind in the winter, though passing over more than a thousand miles of snowy mountains and elevated deserts, is apt to be dry and warm, the snow disappearing rapidly before it. On the other hand a wind from the east is usually more cold and damp. The climate of Colorado is generally favorable to physical vigor and health, there being here few diseases of an endemic kind. Fever and ague are not common, though rheumatic ailments and mountain fever prevail to some extent. A residence in almost any part of the State is so apt to benefit persons suffering from bronchial and pulmonary complaints that it may be considered a sanitarium for this class of invalids.

Nearly all the towns in Colorado are situated in the mountain region, and the remainder are chiefly in the foot-hills. The mountains are crossed by numerous passes. Kenosha Divide is crossed by the Denver and South Park Railroad at the height of 10,139 ft.; Jefferson and Webster stations on that road have respectively altitudes of 9754 and 9120 ft. The city of Georgetown is 8514 ft. above tide; Raton Pass, on the Atchison, Topeka, and Santa Fé Railroad, 7863 ft.; Denver, the State capital, 5197 ft.; Lead-appears to have been nearly as follows: January, 28°; ville, a celebrated mining town, 10,247; Present Help mine, 14,000 ft. There are several mining-camps at or near 10,000 ft. high. Over 500 sq. m. of the State's area are above 13,000 ft., and some 10,000 sq. m. are between 9000 and 10,000 ft. The Argentine Pass is 13,100 ft. high. The lowest point in the State is over 3000 ft. The valleys, many of them deep and narrow, but others wide, are very generally timbered and well watered. When these valleys become very spacious they are termed parks. The North, Middle, South, and San Luis are the largest. The park lands are level or undulating, forming natural lawns, hillsides and dells of great beauty, the vegetation in its season being abundant and botanically interesting. These parks are regarded as former lake-basins, some remnant of the former watered area frequently remain ing. These beautiful mountain walled parks, with their enclosed lakelets, are among the most attractive features of this grandly featured State. Other interesting characteristics are afforded by the cañons, or deeply ploughed channels, along which flow the rivers, chiefly those of the W. and S. W. The walls of these cañons are often perpendicular, and in some cases they incline inwards. The Gunnison or Black cañon winds its way for miles between walls over 3000 ft. high, and from 300 to 600 ft. asunder. Other remarkable cañons are those of the Arkansas and the Uncompahgre. The former is well known to tourists, being traversed by a line of railway which displays astonishing engineering skill and daring. On the W. side of the main mountain-axis are extensive arid plateaus, or elevated treeless plains. Here are also mesa lands, or flat-topped tables of land, bounded entirely or in part by steep scarps, or walls up which it is difficult to climb. These are often well supplied with grass on the top, and are quite frequently of large extent, but water is generally difficult to find. The plateaus and mesa lands generally are from 5000 to 8000 ft. high. A good part of this western versant has been until latterly a reservation for the Ute Indians; and this region is comparatively unpeopled, and some parts are little known to white men.

Rivers and Lakes.-Colorado, like most other regions with many remarkably high mountains, is a grand hydrographic centre. Here rise the South Platte, the Arkansas, the Rio Grande del Norte (all flowing to the Atlantic by way of the Gulf of Mexico, the last named stream directly, the others mediately), and the San Juan, Dolores, Gunnison, White, and Tampah, all principal head-streams of the Colorado of the West, which receives all the waters of the Pacific versant of this State. None of the streams are navigable. Many of the minor streams have cascades of great beauty. The streams of the eastern slope are largely utilized in irrigation works; but many of the rivers and creeks, chiefly in the W., flow in cañons so deep that they can never be diverted into irrigating canals. The presence of lakes or lakelets in many of the mountain valleys has been already noticed. Of these, the lowest is over 7000 ft. high, and Chipayo Lake, the highest, has an altitude of 11,500 ft. The eastern plains are in general but scantily watered.

Climate.-Like all mountain countries this State

There are in Colorado a large number of mineral springs, for which great medicinal virtues are claimed. To some of these springs large numbers of the sick and infirm repair every summer.

Flora and Fauna.-Colorado is tolerably well wooded throughout the mountainous districts, and the country almost everywhere is fairly stocked with animal life. The plains to the east are without trees except belts of cottonwood, aspen, willow, and like inferior timber along the rivers. To supply this deficiency, tree-culture is being practised by the settlers, not yet numerous, in this part of the State. The timber on the foot-hills and mountains consists mostly of pine, spruce, fir, hemlock, and cedar, with a little oak and some other hard woods in the valleys and along the foot-hills. These mountain forests up to an altitude of 9000 or 10,000 ft. are composed mostly of large and stately trees, the growth above this being more sparse and scrubby up to the edge of the timber line, which occurs at a height of about 12,000 ft. Most of the plants and shrubs found elsewhere in the Rocky Mountains or common on the western plains are here indigenous, the country everywhere save in the denser forests being in spring-time covered with wild flowers, bright hued and graceful, but lacking in perfume.

In the zoology of Colorado the buffalo or wild bison stands foremost, immense herds of these animals being found on the lowlands of the State, which have ever been one of their principal habitats. Though

turned out during the past five years in the Leadville | difficulty of reaching them have been but little settled, district has been as follows: 1878, $3,152,825; 1879, this company has to some extent adopted the policy $10,333,740; 1880, $15,025,135; 1881, $13,147,257; of building roads in advance of business and popula1882, $26,000,000. Of the above product about twenty tion, trusting to the growth which would follow cheap per cent. consisted of lead, and the balance nearly all transportation for remunerative returns. Besides of silver, the value of gold amounting to hardly more short local roads this company has completed a railway than one per cent. of the whole. reaching west several hundred miles to Salt Lake City, Utah. The most of the country traversed by this work is rough and mountainous, presenting formidable obstacles to railroad construction. Although railroad building in Colorado, except on the plains, has been attended with heavy expense, these enterprises, by reason of the rapid growth of the country, are likely to prove profitable many of them having already made large net earnings. The total length of track in 1884, including sidings, is 4000 miles, and the assessed value of railroad property is $20,224,293. Over two-thirds of the mileage consist of the stan dard broad gauge, the narrow track being confined mostly to the mountainous districts. In the construction of these mountain roads, some of which reach great elevations, approached over steep grades and through rocky cañons, immense engineering difficulties were encountered, which have, however, been boldly met and skilfully overcome.

As a great number of mines have now been opened and fitted with hoisting and reduction works, and railroads have been built into most of the important mining districts, the metallurgical difficulties that formerly caused so much trouble having, meantime, been pretty well overcome, it may be expected that the bullion product of Colorado will render a marked increase for some time to come. Should an annual increment of ten per cent. be made for the next decade, doubling the present product at the end of that time, it would only fulfil the anticipations of those best acquainted with the resources and the industrial outlook of the State.

Besides gold, silver, and lead, Colorado abounds with deposits of the useful metals; being rich also in nearly every metal of economic value. Some of the more accessible of the deposits of coal and iron have already been extensively and profitably utilized, the iron ore worked being nearly free from sulphur, phosphorus, and other injurious substances, and containing on an average sixty per cent. of metallic iron. These ores are of many varieties: hæmatite and magnetite being the prevailing kinds. The total product for 1882 was valued at $2,650,000. The total product for 1883 was 47,100 tons. The Bessemer Steel Works, erected by the Colorado Coal and Iron Company, at South Pueblo, have capacity to make 30,000 tons of steel rails per annum. This company owns over 100,000 acres of iron, coal, and other mineralbearing lands in the State, and has erected large furnaces at different points for smelting its iron ores: one of these works, the Calumet, near Salida, being situated at an elevation of more than ten thousand feet. While the most of the coal deposits owned by this company are of the bituminous variety, extensive beds of anthracite have been opened up in the Gunnison country which contain over ninety per cent. of carbon. As some of this coal can be coked readily, there have been put up at El Moro 250 ovens that are kept constantly employed in the business of coking. Being cheap and of good quality, mineral fuel is entering into extensive use, being employed not only for domestic purposes but also for generating steam on the railroads and in the crushing mills, many of the large smelters also using it. The coal is, however, of triassic origin. In 1883 the total output of all kinds of coal in the State was 1,220,638 tons. The total production of coke was 149,277 tons. Although copper ores of high grade have been found in many parts of the State, but little has been done with them. Common salt is abundant in Colorado, occurring in springs, on surface incrustations, in numerous places. Sulphur and gypsum are also plentiful, while the finding of opals, chrysolites, and other gems has from time to time been reported. Whether precious stones exist in such quantity as to be worth extended search remains to be determined.

Railroad System.-None of the States or Territories west of the Mississippi have been so well supplied with railroads as Colorado: these avenues of travel and traffic penetrating very generally the eastern, southern, and middle portions of the State. The railways completed and in operation within the State aggregate 2954 miles in length, there being several hundred miles of track projected, some parts of which are in course of active construction. One company, the Denver and Rio Grande, own and operate 1317 miles of railway, and are constantly extending their completed roads, or building additional branches for the accommodation of side localities. Into districts known to be rich in minerals, but which, owing to the

History. As early as 1859 movements began in Colorado looking to the framing of a State government. Accordingly a constitution was that year drafted, but on being submitted to the people for adoption it was rejected. In 1861 Congress organized a government for the Territory. William Gilpin, a member of the Society of Friends, was appointed Governor, and H. P. Bennett was elected Delegate to Congress. In 1862 Gilpin was succeeded by John Evans as Governor. In the next year Congress having passed an enabling act, a convention was held and a constitution framed. This constitution on being submitted to the people was also rejected, but by such a small majority that the effort was renewed in the following year, and the same constitution, with some modifications, was adopted. Congress thereupon passed a bill admitting Colorado into the Union. But this bill having been vetoed by President Johnson, the people were still left under the territorial form of government. In 1875, the State movement having meantime been revived, Colorado was authorized by act of Congress to frame a constitution. done by a convention, and the result ratified by the people, July 1, 1876. On July 4 of that year Colorado was admitted into the Union, and hence is sometimes called "the Centennial State." In accordance with the requirements of its constitution Colorado has no bonded debt. Its total indebtedness on Nov. 24, 1883, consisted of warrants outstanding, $524,045; certificates of indebtedness, $19,833; making a total of $543,881. The revenue of the State for 1883 amounted to $583, 125. The State warrants bear interest at six per cent.

This was

Population, Leading Cities and Towns.-According to the U. S. Census of 1880 Colorado contained 196,649 inhabitants. This number was ascertained to have increased to 219,850 in 1881. The school census taken in 1884 showed the number of persons between the ages of six and twenty-one to be 53,426, and a total population of not less than 312,000. According to local authorities the number of inhabitants in the leading cities and towns of the State was as follows: Denver, capital of the State, 60,000; Leadville, county-seat of Lake county and metropolis of the carbonate region, 25,000; Pueblo, North and South, 15,000; Georgetown, 7000; Central and Black Hawk, 9000; Greeley, 4000; Kokomo, 3000; Lake City, 2500; Silver Cliff, 2000; Silverton, 1500; Trinidad, 3000; Rosita, 2000; Golden, 4000; El Moro, 1000; Cañon City, 2000; Boulder, 5000, there being a large number of agricultural towns, mining camps, and railroad centres throughout the State containing from two or three hundred to a thousand inhabitants each. (H. D.)

COLORADO POTATO BEETLE-COLOR-BLINDNESS.

311

COLOR-BLINDNESS, that is, inability to distinguish separate colors, must have existed from time immemorial, but no record of a case is found with a description of the failure to distinguish colors until 1777, when Mr. Huddart wrote of a man who demonstrated conclusively that he could distinguish only

COLORADO POTATO BEETLE.-This beetle | salubrity, has become a fashionable summer resort. was first described by Thomas Say, from specimens Population, 4226. collected in the region of the Upper Missouri, as Doryphora 10-lineata. Its original food-plant is Solanum rostratum a common western species. As the cultivation of the potato reached the native home of the beetle, this last gradually acquired the habit of feeding upon it, and then began its historic spread towards the East. In 1859 it had reached a point 100 miles west of Omaha, Neb., and in 1864 and 1865 it crossed the Mississippi River into Illinois. In its eastern spread from this point it was a noticeable fact that the southern columns lagged far behind the northern ones. In 1869 it reached Ohio. In 1871 it was found in New York and Pennsylvania, and in 1873 it had reached the extreme eastern limit of these States. In 1875 it arrived at Boston, and in 1876 spread along the sea-coast of New England, extending as far north as Quebec, and south into Virginia.

Its natural history may be thus summed up: It hibernates in the beetle state beneath the surface of the ground or under rubbish. The eggs, to the number of from 500 to 1000, are laid in spring, mostly on the underside of the leaves. The larvæ hatch in less than a week, attain their full growth in from two to three weeks, pupate under ground, issuing again as beetles in a little more than a month from the time of the hatching of the eggs. There are two or three broods in the course of the season, the number depending upon the latitude. Its-food-plants include most of the Solanaceae, and when hard pressed it will feed for a while on the garden cabbage, the common thistle, and many of our common weeds. Among its natural enemies may be mentioned several species of insectivorous birds, several spiders, a mite, which has been described as Uropoda Americana, two or three species of wasps, a number of the useful little Ladybirds (Coccinellida), many species of Groundbeetles (Carabida), and Tiger-beetles (Cicindelida), a species of Rove-beetle (Philonthus sp.), many of the soldier-bugs, a Tachina-fly (Exorista doryphora, Riley), and an Asilus-fly (Protocanthus milberti, Macq.).

Remedies.-Where the "potato-bug" is to be fought in small gardens, many are led, from fear of the poisonous qualities of Paris Green, to prefer the more laborious method of hand-picking. The beetles are crushed with gloved fingers, or are knocked into pans and then destroyed with hot water or kerosene. The use of London Purple or Paris Green, mixed with flour or dissolved in water, will, however, be found the cheapest and most efficacious of all proposed remedies, and it has been repeatedly shown that the danger from the use of these poisons may, with proper care, be reduced to almost nothing, since they do not influence the soil and are not absorbed by the plant. Paris Green may be diluted with from twenty-five to thirty times its weight of flour, and still be efficacious, and, dissolved in water, the proportion is, roughly, one tablespoonful of the Green to a bucketful of (c. v. R.) COLORADO SPRINGS, the county-seat of El Paso co., Col., is on the Denver and Rio Grande Railroad, 10 miles east of Pike's Peak, and 75 miles south of Denver. It has 3 banks, an opera-house, 2 daily and 3 weekly newspapers, 9 churches, good public schools, and is the seat of Colorado College, and of the State Institution for deaf-mutes and blind. It contains the offices of the Denver and Rio Grande Railroad, and the Colorado Coal and Iron Company. It has water-works, gas-works, a telephone system, a good system of irrigation. It was founded in 1871 by Gen. W. J. Palmer, and, on account of its beauty and VOL. II.-S

water.

Ъ

Colorado Potato Beetle.

D

white and black. He could not name nor match any of the various colors placed before him. He could not discern fruit by its color on the trees but only by the shape.

In 1779 a Mr. J. Scott wrote that he was unable to see colors as others see them. In 1794, Dalton, an English chemist, gave a description of his own inability to distinguish red from green, which attracted some attention at that time, so that this chromatic defect was called "Daltonism." Even after this publication the defect was little noticed, being classified as one of the rare anomalies of vision. No attempt was made to examine the mass of the people to see to what extent it could be found. Only two further cases were reported: one in 1816 and the other in 1818. Only within the past few years has proper attention really been drawn to it, and interest enough taken to examine the people for the estimation of the percentage among them of this chromatic defect, and to study its causes and effects in relation to man's dangers and inconveniences therefrom.

This attention arose by the discovery, on investigating the causes of some railroad accidents, that the engineers did not and could not distinguish the signals of danger that were displayed. This caused scientific men to make general examinations of train-hands for the elucidation and explanation of some of the unaccountable accidents that had occurred upon the railroads. The discoveries were so interesting that these examinations soon extended throughout the schools to find out the ratio of defect, as well as grades of defect, among the children. Naturally, from these examinations, some general laws and classification of this peculiar visual condition have been deduced.

Prof. Holmgren, of Upsala, Sweden, was the first to go thoroughly into the examination and physiological study of color-blindness. He accepts the YoungHelmholtz theory of Color-perception (see EYE in the ENCYCLOPÆDIA BRITANNICA), "That nerve-fibres in the retina are excited by waves of light, and the development of color arises from the action of longer or shorter waves upon certain fibres, producing the sensation of a color according to the length of the waves. Long waves excite fibres sensitive to red; medium, those sensitive to green, and short, those sensitive to violet." He says, "That color-blindness in each case is a genuine blindness to one of the primary colors, and that therefore three classes of blindness are to be distin

guished: Red-blindness, Green-blindness, and Violet | are re-sorted correctly. In such cases the color per(blue) blindness.

Red-blindness is due to the absence or paralysis of the nerve fibres or organs perceiving red, leaving but the two fundamental colors, green and violet. According to Helmholtz: "Spectral red feebly excites the perceptive organs of green and less so those of violet, and consequently to a red-blind person red appears a saturate green of feeble intensity into which a sensible portion of the other colors enter. Feebly luminous red does not sufficiently excite the perceptive organs of green in the red-blind, and it seems then black. Spectral yellow seems to them green and intensely luminous, and thus causing them to call all green tints yellow. Holmgren shows that it is clear that a red and green light excite one and the same element in the red-blind, and an object of these colors must appear of the same color.

Green-blindness arises from the absence or paralysis of the perceptive elements of green; leaving but two fundamental colors, red and violet. The spectrum of a green blind is: the red appears as an extremely saturated red, but somewhat less intense than the normal red which is more yellowish, as green forms part of it. Blue is violet, and violet is less intense than normal. The tints most luminous to the green-blind are orange and indigo blue, while red and green are the same color.

Violet-blindness is due to the absence or paralysis of the elements perceiving violet, leaving the two fundamental colors red and green. To such the red is purer than normal; yellow is as a combination of the primitive colors that form white. Green is strongly luminous, but whiter; blue is a green of moderate luminosity, and violet is a feeble green. To the violetblind red and green are not confused.

Violet-blindness is very rare, while red and green are comparatively common. The greatest number found is that of red-blind.

Holmgren has divided this chromatic defect into three grades of intensity:

nerve.

ception, though slow, is otherwise normal.

Of the examinations now made throughout the world, in the schools and in the railroads, about 3.5 per cent. of males are born color-blind, while in females only about 1 per cent. has been found.

To the red and green-blind, black, white, yellow, and blue are generally clear and distinct, and seen as others see them. The red-blind person sees lower-tone red shades up to crimson, in yellowish tints; and then a gray or colorless hue presents itself in the brighter or higher tones of crimson. When the red shade runs into a lake, a bluish tint comes on, and increases in value as the red runs into violet. With the greenblind, the green when pure is invisible, and appears gray; but when it is mixed with yellow or blue (as most greens are), the patient sees those elements only,

A violet-blind person will lose the yellow in reds and the blue in greens, according to the shade of the violet, whether on the yellow or bluish order, so that a reddish-violet will look clear, sharp red, and a bluishgreen will be a clear, distinct green. But if the violet is feeble in tone it becomes black.

For the more thorough study of color-perception and color-blindness, consult especially Helmholtz Physiologische Optik (1867), Kaiser, Compendium des Physiologische Optik (1872), Holmgren, De la Cécitè des Couleurs, etc. (1877), Translation by the Smithsonian Institute (1878), Jeffries, Studien über Farbenblindheit (1879), etc. Color-blindness, Its Danger and its Detection (1879), Cohn, (P. D. K.)

COLTON, CALVIN (1789-1857), an American minister and author, was born at Longmeadow, Mass., in 1789. He graduated at Yale College in 1812, studied theology at Andover, and was ordained in 1815 as a Presbyterian minister at Batavia, N. Y. On account of the failure of his voice he gave up preaching in 1826, and became a contributor to the press. In 1831, after having travelled through the United States, he went to England as a newspaper correspondent. Ďuring his residence there he published The Americans, by an American in London, and other books, to diffuse 1. Total color-blindness (Achromatopsia). A con- more correct ideas with reference to the people and dition in which there is entire absence of the per- institutions of the United States. Returning to New ception of colors. Only black and white and the York in 1835, he published Four Years in Great Britdifferent degrees of intensity of light can be perceived. ain, and soon after an anonymous work called ProtestEverything looks in black and white like a photo-ant Jesuitism, attacking the course of some prominent graph. This grade is very rarely found congenital, religious societies. His next work, Thoughts on the but mostly follows some disease of the brain or optic Religious State of the Country, and Reasons for Preferring Episcopacy, published in 1836, was occasioned by his change of church relation. After 1838, for several years, political subjects chiefly occupied his attention, and his writings were considered a valuable aid to the Whig party. He opposed the abolition of slavery, which then began to be urged by the Liberty party, and favored the colonization movement. His Life and Times of Henry Clay was prepared with the sanction and assistance of that great statesman, and published in 1845. In the same year Colton wrote The Rights of Labor, and in 1848 a larger work on Public Economy in the United States, advocating the protective system. In 1852 he was made professor of political economy in Trinity College, Hartford. He died March 13, 1857, at Savannah, Ga., whither he had gone on account of failing health. His last literary labor was connected with his complete edition of the Writings and Speeches of Henry Clay. Mr. Colton also published The Genius and Mission of the Protestant Episcopal Church in the United States.

2. Complete color-blindness (Partial Achromatopsia). In which there fails the perception of one of the fundamental colors, red, green, or violet; in this group is classed red-blind, green-blind, violet-blind; and generally the congenital cases can be placed here. One born color-blind will always remain so, no matter how assiduously he attempts to educate his eye. He will not be able to see the colors in the normal way nor with the normal promptness. He does not really see the color, although he may make some kind of a distinguishment by the intensity or luminosity, and this power of distinguishing may sometimes be improved by practice.

3. Incomplete color-blindness (Dyschromatopsia). This is more frequent-this is complete "Daltonism, and consists in a reduced sensitiveness in recognizing some one or more of the fundamental colors, and especially the shades of that color, even when the primitive color may be distinguished. The perception is not so sharp and clear in certain shades as in others. This grade of defect can be very greatly remedied by education.

Magnus, of Breslau, has added a fourth grade of color defect, which he calls "Dullness or sluggishness of color distinction" (Farbenträgheit). This defect is characterized by the person first sorting out colors, by laying many shades of different colors together, just as he would do if color-blind; but, on examining them again to see if correct, the mistake is noticed and they

COLUMBIA, the county-seat of Boone co., Mo., is the terminus of the Columbia branch-22 miles long of the Wabash, St. Louis, and Pacific Railroad, and is 140 miles west of St. Louis and 10 miles north of the Missouri River. It has a court-house, 2 national banks, 3 weekly newspapers, 1 monthly and 2 quarterly reviews, 7 churches, 2 female colleges (Stephens and Christian), public schools for white and for colored children. It is the seat of the University of the State of Missouri, which was founded