Exceptional Meteorological Conditions in the Niobrara River Region.--The exceptional physical features already noticed in this region no doubt help to produce the exceptional meteorological conditions. In this region during the summer months, there are almost daily thunder showers. There is little snowfall in winter, but when the hot weather approaches, these thunder showers are very frequent. This has occurred whenever it was my fortune to be there The morning sun would appear with wonderful clearness, and the heat would become intense by 2 o'clock, and then in a few minutes clouds would form and thunder peal. After the outpouring of the clouds, which generally lasted from thirty minutes to an hour, the clouds would vanish and the sun appear. Frequently there was another thunder shower during the early hours of the night.

   The cause of these frequent showers appears to me to be this: At the head of the Elkhorn and the Loups, and between these rivers and the Niobrara, there are great numbers of small lakes and ponds and sloughs. These are underlaid by an impervious clayey stratum, so that the only escape possible for the waters is by overflow and evaporation. Some drain into these rivers, but many have no visible outlet. Near to and among these lakes are the Sand Hills. The sun shining on these hills heats them up to an extreme degree, and necessarily also the atmosphere around and above them. I have experienced a temperature myself here in the shade of 110° Fahrenheit, when the register at Plattsmouth marked only from 85° to 90° Fahrenheit. The consequence is that the evaporation is enormous. The atmosphere becomes supersaturated with moisture. The least fall now in temperature, produced by a change of wind or other cause, creates cloud, the play of lightning, and rainfall.

   Comparative Estimates with Other Regions--Europe.--While many will admit that there is an abundance of rainfall east of the 100th Meridian, they still claim that west of that line it is too dry for the successful production of anything but stock. They point to the less amount of rainfall west of that line, and ask how a region that receives so little can be utilized for agricultural purposes. Two replies can be made.

   The fallacy of this conclusion can be seen at once if we compare the rainfall of Western Nebraska with that which obtains in some of the most favored spots of the Old World. The following table I have taken from Guyot:

                 TABLE OF RAINFALL.
                                    Depth in
                                     Inches.

     British Islands. . . . . . . . .  32 
     Western France . . . . . . . . .  25 
     Eastern France . . . . . . . . .  22 
     Sweden.. . . . . . . . . . . . .  21 
     Central and North Germany. . . .  20 
     Hungary. . . . . . . . . . . . .  17 
     Eastern Russia (Kasson). . . . .  14 
     Northeast Portugal . . . . . . .  11 
     Madrid . . . . . . . . . . . . .  10

   Paris itself, according to the researches of Arago, has only an average annual rainfall of twenty inches. (Cosmos, Vol. 1, p. 331.)

   Now, it is true that there are many rainy days in Western France (152) and in Central and North Germany (150); yet, if we count in the nights when it rains, and the days and nights when it snows, there is not so much difference as at first imagined between the wet days of Nebraska and Middle and Western Europe. Regions in Europe with less rainfall than even Western Nebraska are made successful in agriculture. Less toil than is expended to make the dry portions of Europe a garden would make Western Nebraska agriculturally rich. Even, therefore, judged by European standards, Western Nebraska is already sufficiently watered for the needs of certain kinds of agriculture.

   Now, it is true that there are many rainy days in Western France (152) and in Central and North Germany (150); yet, if we count in the nights when it rains, and the days and nights when it snows, there is not so much difference as at first imagined between the wet days of Nebraska and Middle and Western Europe. Regions in Europe with less rainfall than even Western Nebraska are made successful in agriculture. Less toil than is expended to make the dry portions of Europe a garden would make Western Nebraska agriculturally rich. Even, therefore, judged by European standards, Western Nebraska is already sufficiently watered for the needs of certain kinds of agriculture.

   The second reply to those who object to the little rainfall in Western Nebraska is that the rainfall is increasing from year to year. This fact will be considered in the next section.

   Increasing Rainfall and its Sources.--The appearance of new springs where they had never been noticed before is a common phenomenon in Nebraska. This has particularly been observed along the Missouri River bluffs, and along the bluffs that border the flood plains of most of the rivers of Nebraska. My own partial record of new springs now numbers over two hundred, that have appeared within twelve years. Connected with this same line of facts is the phenomenon of the appearance of water in old creek beds where it apparently had not been flowing for ages. Many of the tributaries of the Elkhorn and Niobrara, the Logan, the Bows and Loups, with beautiful bottoms, and old stream beds in the middle or on one side of them, and which were perfectly dry when I first visited them in 1865 and 1866, are again living streams. Many of them that had grass grown over them, which were even difficult to find, so nearly obliterated were they, are again permanently supplied with water.

   The increasing size and depth of the streams of the State, which old settlers observe, points in the same direction.

   The changing vegetation of the State proves the same fact. Until quite recently, the buffalo grass was the most conspicuous vegetable form west of the Missouri. When Lewis and Clark passed up the Missouri in 1804, it was almost the only grass that they found growing along that portion of their route. Fremont observed the same thing se late as 1842. The first settlers in this territory found it abounding along all the river counties. The early freighters across the plains depended most on it for pasturage for their cattle. Now, how changed! It has almost entirely disappeared for 200 miles west of the Missouri. There is comparatively little of it now on the third hundred. Every year it is retreating farther westward. Its place is supplied with grasses indigenous to moister climates. Where formerly the ground was covered with grasses from two to four inches high, there is now a carpet of green from six inches to four feet high. Many of the blue joints and sorghum grasses exceed even this height. Still other forms besides the grasses, characteristic of moist regions, are occupying the spaces left by the retreating buffalo grass. There is also an increase in the spontaneous growth of timber. Wherever there are abandoned cultivated fields, and the prairie fires are kept away, and the tract is left unmolested from other hindering causes, thick growths of cottonwood and sometimes box elder frequently soon monopolize the ground. This is especially true of lands in close proximity to existing timber belts. There is an increasing disposition to do this all over Eastern Nebraska. Where formerly there was not sufficient moisture to start the seeds into life on the high lands, which are scattered each year by the winds, birds and rodents, there is now an abundance. In fact, it is questionable if prairie fires were entirely repressed, whether groves of timber would not now gradually creep all over the unoccupied lands of Nebraska. The proofs, therefore, that the rainfall of Nebraska is steadily increasing are manifold. If space permitted, many more could be given. It is therefore probable that the early explorers of this region were correct in ascribing to it a partially desert character. And yet even then they could only have been partially correct. No desert can support countless thousands of buffalo, elk, deer and antelope, as the plains of Nebraska did when Lewis and Clark made their first voyages of discovery up the Missouri. The probabilities are that those eminent explorers confounded the appearance of a section closely pastured, and in some places made bare by the pasturing, of those immense herds of buffalo of which they speak, with the barrenness that a true desert always exhibits. A land that is supplied with sufficient moisture in such a climate as this, to produce food for such an affluence of animal life, can always be made available for the purposes of a high civilization.

   Causes that are Producing the Increased Rainfall of the State.--Various causes have been assigned to account for the increased rainfall of the State. Some have maintained that the cause is secular--that there are great periods when the moisture of a region increases for ages, independent of any human agency, and that when it has reached a maximum, it commences to decrease, which continues until it reaches a minimum. According to this theory, this region is now in such secular change of increasing moisture.

   Another plausible theory is that the planting of trees has been the cause of increasing rainfall. This, I admit, is a helping cause, but cannot be the main cause. Here there was an increase of rainfall, before the number of trees planted equaled the number destroyed. The statistics of forestry show in the East, in Europe and Asia, that forests modify temperature, the violence of winds, and equalize rainfall, but do not increase it. While, therefore, the growth of forests exercises the happiest influence on climate, it is evident that we must look elsewhere for the permanent cause of increasing rainfall There is, however, another cause, not heretofore mentioned, most potently acting to produce all the changes in rainfall that the facts indicate have taken place. What then is that, cause?

   It is the great increase in the absorptive power of the soil, wrought by cultivation, that has caused, and continues to cause, an increasing rainfall in the State.

   Any one who examines a piece of raw prairie closely must observe how compact it is. Every one who opens up a new farm soon finds that it requires an extra force to break it. There is nothing extraordinary about this. For vast ages the prairies have been pelted by the elements and trodden by millions of buffalo and other wild animals, until the naturally rich soil became as compact as a floor. When rain falls on a primitive soil of this character, the greater part runs off into the cañons, creeks and rivers, and is soon through the Missouri on its way to the Gulf. Observe now the change which cultivation makes. After the soil is broken, the rain as it falls is absorbed by the soil like a huge sponge. The soil gives this absorbed moisture slowly back to the atmosphere by evaporation. Thus year by year, as cultivation of the soil is extended, more of the rain that falls is absorbed and retained to be given off by evaporation, or to produce springs. This, of course, must give increasing moisture and rainfall.

   To test the accuracy of this theory, which struck me as the only adequate explanation of this phenomenon, I commenced to make experiments as early as 1867. The following were a few of those experiments. East of the Antelope, a mile from Lincoln, after a heavy rain, a square foot of soil was taken up three inches deep from unbroken prairie, and placed in a porcelain dish that had been previously weighed. The same amount to the same depth was taken from a cultivated field a few yards off. The difference in weight between these two specimens, after being weighed, then dried in a drying oven, and then weighed again, showed that during this rain the cultivated ground had absorbed ten times as much water as the unbroken prairie.

   Where the rainfall is slight, the difference will not be found so great. Much also depends on the lay of the land; care must also be taken that the cultivated land that is experimented with lies adjoining unbroken prairie, as there is often considerable difference in rainfall, especially in thunder storms, in the space of a quarter of a mile. In all cases the experiments were made immediately after or during the intermissions of rainfall. After only slight rains, the difference in absorptive power was only as four to one. The mean, however, of fifty of these experiments, gives an average absorptive power of cultivated ground over unbroken prairie of nine to one. To make allowances, how ever, for possible mistakes, I will make eight to one the basis of our future calculations on this subject.

   When the first settlements were commenced in Nebraska, the rainfall of the State was not over twenty inches. Of these twenty inches probably not more than five inches soaked into the ground. Cultivated soil, however, absorb nearly all the rain that falls. Where thirty-two inches of rain now falls in Nebraska on cultivated ground, not less than twenty four inches are absorbed by the soil Some of this is slowly given back into the atmosphere, and some of it goes to form the new springs of water that are making their appearance in so many places. Any one can see that this must make an enormous difference in the moisture of the atmosphere and on rainfall. Before the settlement of the State, and before the consequent cultivation of the soil, what rain did fall, as already stated, soon left the State through creeks and rivers. Now the greater part of what does fall on all cultivated or broken ground, is retained by the soil, which becomes a reservoir of water to supply growing crops, and to give greater humidity to the atmosphere.

   Absorptive Power of Nebraska Soil.--The soil of Nebraska has a maximum of absorptive power. The superficial deposits, largely made up of silicious and calcareous materials, is very thick. The thickness of the loess is itself from 2 to 200 feet. The average thickness cannot be less than 100 feet. This, then, is a huge natural sponge that absorbs excessive rainfall, and retains it to be gradually given back to the atmosphere.

   Cultivation, therefore, opens the door through which the rain that falls enters the deep reservoirs, and is stored there, from which stores the atmosphere is gradually sup plied with needed moisture for additional rainfall.

   Through the operations of this cause, the rainfall will become even more abundant than it has yet been, especially over the central and western portion of the State. The area of cultivation is extending rapidly each year, and continual encroachments are made on the lands in Western Nebraska, that have been condemned as barren, because of a deficiency of rainfall. Last year a large amount of land breaking was done, near to and west of the 100th Meridian, in the Republican Valley and the table lands adjoining it. It is extremely probable that the causes that are now producing increased rainfall over Eastern Nebraska, will eventually prove operative to the west line of the State, and eventually will bring the whole of it under agricultural subjection.

   Sources of the Rains of Nebraska.--These are twofold. One source is the moisture-ladened winds from the Gulf; the other is the enormous evaporation from those rivers of Nebraska that have their source in the Rocky Mountains.

   Rain is most apt to fall when there is a change in the direction of the winds, especially if the change is from the north or south. The south wind coming directly from the west end of the Gulf of Mexico, strikes Red Willow, Furnas, Dawson, Custer, Elkhorn and Knox Counties. Whenever, therefore, all Nebraska, including these and the counties east of them, are bathed by this moisture-bearing wind from the Gulf, either after a north wind or followed by one, there is a precipitation of moisture into cloud, and generally rainfall. When the wind is slightly from the southeast, extreme Western Nebraska also shares in the rainfall; otherwise, it does so only to a very limited extent. This is one reason why there has been less rainfall in this section than in Eastern Nebraska. It is probable, however, that with the increased cultivation and increased average rainfall that comes with it, in Eastern Nebraska, Western Nebraska will gradually approximate to an increased rainfall sufficient to produce successfully the cereal grains, grasses and Indian corn.

   The second source of rainfall for Nebraska is the moisture from the rivers that flow from the mountains. These rivers are the Platte, the Niobrara to a small extent, and the Missouri and its tributaries. The flood time of these rivers is always a rainy season for Nebraska. This rainy season comes earlier or later as the " big rise" is earlier or later. Then the moisture that is wafted here by the winds from the Gulf, is re-enforced by the moisture that is evaporated from these rivers; and the consequent precipitation into cloud and rainfall, constitutes the rainy season for Nebraska. A map of Nebraska shows how two of these rivers run the whole length of the State, and that the mighty Missouri is east and north of it. The Missouri, too, it should be remembered, has a course of 400 miles along Eastern Nebraska, for, though the State is little more than 200 miles from north to south, the serpentine windings of the river give it at least double that length. We have, therefore, a length of 400 miles of the Missouri and (for the same reason as applied to the Missouri) at least 600 miles of the Platte, or 1,000 miles of river, averaging one mile broad, or 1,000 square miles of rapidly moving river surface, exposed to a warm atmosphere, from which the evaporation is simply enormous. The Niobrara, counting its windings, adds 500 more miles of evaporating surface. Unlike the floods of Eastern rivers, these "big rises" last for a considerable length of time, often indeed from its beginning to its close, over two months. What adds greatly to the rapidity of the evaporations is the difference of temperature between the waters of these rivers and the atmosphere. Lewis and Clark, during their famous expedition up the Missouri, in 1804, spoke of the sameness of the temperature of the water of the Missouri and its tributaries with that of the atmosphere. If no difference existed then, it does now. For example, the signal service at Omaha, for June, 1878, report a mean temperature of 68° 4'. This shows that the temperature of the water for this month is considerably lower than that of the atmosphere. The Missouri River temperature is also 2½° lower than that of the atmosphere in July. At North Platte there is still greater difference between the temperature of the river and that of the atmosphere. The temperature of water is always much more uniform than that of the atmosphere. From all these causes the amount of evaporation is very great and the winds carry the moisture in various directions, until finally it is again deposited as rain.

   Nebraska Affected by the Amount of Precipitation on the Mountains.--As the magnitude of the rainfall is dependent on the length and magnitude of the river floods, and these latter are dependent on the snows of the mountains, it becomes an important question whether the present amount of precipitation there is stationary, increasing or decreasing. In extended travels and explorations in the mountains, I have seen no evidence tending to show increasing aridity. Some have claimed that where forests are removed, nature no longer restores them. On the contrary, I have seen very many places where the mountains were stripped of timber covered by a dense growth of young trees. In my observations, this was invariably the case where nature was given a chance by the repression of fires and the withholding of cattle, that so frequently destroy growing sprouts. I am satisfied, therefore, that as yet there is no evidence indicating that the mountains are receiving less rainfall, but rather, if any change is taking place, that precipitation of moisture is there on the increase.