did quite well because it will always do well on well drained soils, even if pretty poor, for to some extent the theory that it makes its own fertilizer seems true. But the food the trees demanded was leached away by the constant run of water, making trees and fruit both small although the trees were lightly loaded; while the trees, sickened by having the roots all the time too wet in spite of the drainage, could not produce good fruit even on rich soil. As I remarked in the beginning of this work, bad irrigation is generally far ahead of no irrigation, even in those countries where so much can be raised on the rainfall as to make people feel insulted when you advise them to irrigate. Yet nothing Yet nothing THE is more foolish than to follow the methods IRRIGATION AND SUBSOILING. 'HE conservation of moisture in the semi-arid States, is quite as important a problem as is that of securing the benefits of irrigation in States where this has not yet been practiced. In the Gallatin valley, the acknowledged peer of all agricultural development in Montana, if not, indeed, of all sections of the mountain States, land is cheap and abundant, and the practice of summer fallowing is quite universally practiced. In There are large areas of bench lands above the water course level, on which crops are grown uniformly successfully by summer fallowing each alternate season, winter grains being the common crop. the valley proper it is the general custom to summer fallow every third year, alternating the two seasons to oats and barley, or wheat and barley, and occasionally to wheat and oats. By this practice they are able to uniformly grow crops double and treble those in States where water is not used. There are well-grounded objections to this style of farming, especially where irrigation can be practiced. It is an expensive way to farm; the land usually becomes weed-sown, and scientists teach that it is injurious to soil to turn it up to the summer storms and sunshine unprotected by verdure, and taxes and, too often, interest are being assessed, whether the land *Director of the Experiment Station. more Yet is producing or not. By personal inquiry it was learned that the average of fallowed land in the Gallatin valley in 1895 was than 100 acres per farm. This affects quite seriously the question of additional water, when the time comes, as it most certainly will, for yearly cropping of all Montana farm lands. Had the entire area of land under plow in this valley been sown to grain crops in 1895, there would have been many crops injured from lack of sufficient moisture. DIVERSIFIED CROPS. The Experiment Station Farm is being cropped, every foot of it, each year, and though there is a water right of 100 miners' inches to 185 acres, it is ample for the farm requirements. Crops are diversifiedalfalfa, clover, field peas, potatoes, mangels, carrots are favored crops. In grains wheat, oats, barley, flax and rye are leaders. By thus diversifying, the use of water may be protracted at each end of the grain irrigating season, the grasses and clovers being watered weeks ahead of the grain crops; again, fall irrigation has been practcied with the intent to store moisture against the day of need. The writer has been strongly impressed with the importance of deep culture, and is now reaping a mis-benefit therefrom in a phenomenal crop of wild sunflowers on lands which for two years past have not ripened a sunflower seed. Evidently the seed have lain dormant in the soil for four or more years, deeply buried by an extra deep plowing in the fall of '93 and resurrected the present spring by a similar course. Deep plowing, as ordinarily practiced, is not satisfactory where there is heavy clay subsoil; too much subsoil is exposed on the surface. This is doubly bad where water is applied to grain crops as the clay will dissolve, puddle the surface of the ground and bake so hard that a second irrigation brings little relief to the crops. BENEFITS OF SUBSOILING. In 1895, ten acres in which potatoes were to be planted were subsoiled to a depth of eleven inches. The single subsoil plow was used, drawn by three horses, and following a turning plow also drawn by three horses. Considering that two men and six horses were employed, and that one and a half acres per day was a daily average, it was expensive work. In irrigating it was found that much more water was required to submerge the soil than on lands not subsoiled. This piece of land is now sown to barley, and gives promise of being an extraordinary crop. (The tract has never been manured to the best of our information.) Upon receiving a prospectus of the Secretary plow, made by the John Deere Company, one ordered and has been used upon fifteen acres of spring plowing. was This plow is a combination of the disk and subsoil plow, and, by a single operation, the ground is subsoiled each two inches in ten, and the top soil completely pulverized by the action of the disk plow. Its strongest point is that the wedge principle involved in all turning plows is applied only to the two-inch strip under the subsoiler, the disk working above the subsoiler, and cutting and partially turning ten inches, while the subsoiler works two inches in width. The application of water to the soil thus treated this spring will be watched with the keenest interest and it is a foregone conclusion that it will absorb at least double the amount of water that soil fitted with the old-style turn plow does. To get the full effects of such moisture deposition, it should be coupled with a high state of preparation of soil prior to seeding, so complete as to pulverize all clods and lumps; subsequent to seeding, the ground should be rolled to compact the surface and hasten germination, and prior to the appearance of the young blades of grain the ground should be gone over with a fine tooth harrow each way, so as to supply a dust blanket to prevent undue evaporation of moisture. It is of the utmost importance that water be used at the earliest possible moment after grain is well up. There is then an abundance of water and, unless storage reservoir facilities are provided, the farmer must daily see water run to waste, the use of which in a very brief time would mean a difference between failure and success. Upon this same subsoiled land, wellrotted barnyard manure is now being applied upon growing grain crops with the Kemp & Burpee manure spreader. This gives an even distribution of manure, no lumps being thrown out, all such being well pulverized by the revolving cylinder, armed with sharp pointed teeth which tear all lumps to pieces. This spreader was used in 1895, until the grain began to joint, and though it seemed as if the battered and bruised grain would never recover from the severe treatment inflicted in driving the wagon over the fields; yet, in three days time after the application of the water, one could not tell where the spreader had gone, save by the deep rich color and the rank growth of the grain. Subsoiling, thorough preparation of the soil before and after seeding, a diversity of crops, the use of clovers and root crops, and top dressing of grain fields must all be practiced by him who expects to make the most of a limited water supply. To one unaccustomed to the use of water it may seem paradoxical to urge a course that will require more water to saturate the soil. It is, however, true "the more haste the less speed" in this case. One should endeavor to make a crop with one irrigation, as it is exceedingly difficult to make up to crops by a second irrigation that which they have failed to receive in the first use of water. In mountain regions the second or third irrigation has a tendency to unduly prolong the growth of grain and to expose it Hence to the ill effects of early frosts. the important part played by deep culture in the conservation of moisture. WATER SUPPLIES FOR IRRIGATION. CHAPTER VI. STORAGE RESERVOIRS, EVAPORATION AND PERCOLATION. BY F. C. FINKLE, C. E. UCH surveys and examinations as will give a complete description of the character and condition of the watershed should be made. The points to be noted. are the slope and pitch of the surface at different places, the character of the surface formation, the range of elevations and the amount and class of vegetation. All observations of this character furnish data from which the value and capacity of a watershed can be estimated. The ability of a watershed to furnish water for storage depends upon the matters which we have already discussed, i. e., the area and character of the watershed and the amount of annual precipitation thereon. The old school of hydraulic engineers were wont to assume that the discharge of water from a watershed, available for storage, was equal to onehalf of the total annual rainfall on the watershed. While it is true that this was the general assumption, still there were many who depended more on their own judgment as applied to each individual case. This latter method is not entirely unsatisfactory as the judgment of one well versed in hydrology, when he is acquainted with the geological structure, extent and physical characteristics of a watershed, is usually able to grasp its capacity for yielding an available water supply, by deciding what proportion of the rainfall will be discharged and what proportion will be lost in various ways. But neither of these methods are satisfactory for making close and accurate estimates, and since statistics have been collected from observations made and recorded by government bureaus and hydraulic engineers, the matter has been reduced to more of a science. The observations from all points do not exactly correspond, which makes it difficult to produce a formula which will give results for all places. It appears that results obtained from localities where the distribution of the rainfall is uniform throughout the year, are somewhat different from those obtained in regions where the year is divided into a rainy and a rainless season. Our investigations being in the interests of irrigation, we will devote ourselves to constructing a formula formula applicable to regions with the year divided into a wet and a dry season. FORMULA FOR STORAGE SUPPLY. By plotting such results as have been collected from observations made in irrigated localities or localities requiring irrigation, where the distribution of the annual rainfall is somewhat irregular, the resultant has been found to follow very closely the following formula: Q=Ax pcf, in which = Q the number of cubic feet of water discharged during the year. A area of watershed in square feet. p = percentage due to character of watershed. c = a variable factor depending on the annual depth of rainfall. f = the depth of annual rainfall in feet. The percentage due to natural characteristics of the watershed and represented in the formula by the factor p varies from .30 to .85. The mean values are as follows, and for cases not corresponding exactly to the descriptions given, values intermediate to those given can be assigned in actual prac tice: For steep, rocky hills and mountains from .75 to .85. For heavily timbered bills or mountains and moist brushy and swampy lands from .65 to .75. For rolling grassy brush or timber land from .50 to .65. For tolerably flat or gently sloping alluvial plains, with little grass and brush from .40 to .50. For flat or gently sloping cultivated lands from .30 to .40. The variable factor c has the following values: For an annual rainfall of 40 inches or upwards. ; for 30 inches, ; for 20 inches,; for 10 inches, ; for less than 10 inches, The values of c intermediate to those given can be found by simple proportion, and all values when used in the formula should be written in per cent decimals, which are better adapted to logarithmic computation. From the recorded observations and the formula deduced therefrom, it is patent that a large portion of the water falling from the clouds does not flow off on the surface of the ground. This water becomes lost in various ways, or in other words goes where it is not visible in channels on the surface, nor can it be collected to fill storage reservoirs. A portion of it is evaporated, and returns to the air to again fall as rain; a portion is consumed by the growth of vegetation, and the remainder, which is by far the greatest portion, sinks into the ground and goes to constitute underflow of streams, subsoil water, spring water, and the water contained in artesian strata. When it is possible to do so it is always advisable to measure the daily discharge of water from a watershed, in addition to making a survey of it and gaugings of the rainfall. By doing this it is possible to determine accurately what is the actual quantity of water running off on the surface without the inaccuracies and uncertainties which are always involved in theoretical formula and calculations. Usually the cost of measuring discharges from streams is quite great in comparison with the cost of gauging the rainfall, and for this reason it can not be carried on so easily nor for any great length of time, unless in exceptional cases. In all cases, where it is possible to do so, the discharge should be measured and the rainfall gauged as well for at least one year. this way the variable factors in the formula can be given fixed values applicable to the watershed in question, and the formula In " can be so expressed as to eliminate all elements of uncertainty, so that perfect results for the watershed in question can be obtained for subsequent years, although observations of the rainfall alone are made. EVAPORATION AND PERCOLATION IN STORAGE RESERVOIRS. All the water accumulated in storage reservoirs can not be applied to useful purposes. There are certain losses causing shrinkage in the volume of water after it is impounded, which must be deducted before the amount available for use can be ascertained. The two principal means by which water is abstracted from a storage reservoir are evaporation and percolation. The former of these can, in ordinary cases within the region where irrigation is practiced, be considered to equal the amount of rainfall on the surface of the reservoir. At all events it is perfectly safe to make this assumption, as the rainfall on the surface of the reservoir is more likely to exceed the evaporation than not to equal it. Of course, when evaporation is accounted for in this way, the area of the impounding basin must be subtracted from the total tributary watershed above the dam site, in making the surveys and estimates of available watershed for filling the reservoir. The amount of percolation is a more difficult matter to arrive at, as the soil comprising the basins of storage reservoirs may be of any conceivable nature. Very often ledges or veins in the sides of the basin may convey a considerable amount of the water impounded away to points below the dam. In cases of this kind, where the loss of water is great, it can readily be noticed and remedied. If the water entering the reservoir is heavily charged with silt and sediment, the difficulty may remedy itself. The most dangerous species of percolation, however, is that which finds its way into entirely underground channels and can not be noticed except for its effect in diminishing the water in the reservoir, as its reappearance takes place so far away that it can not be easily detected in this way. The only way of determining its amount is by accurately measuring the water drawn from the reservoir, while observing the exact quantity disappearing from the reservoir during the same time, as well as the quantity entering it if any. In faultily constructed dams there is sometimes a loss by percolation through the dam, but in works properly planned and carried out, the loss on this account, if any at all, should be so small as to be of no practical consequence. SUMMARY OF NECESSARY SURVEYS. Considerable reference has already been made to surveys necessary in the investigations relating to storage reservoirs. A summary or recapitulation on this point may not be amiss, as the subject is one of great importance. The following are the principal details, which should in all cases be covered by such surveys: The area of the reservoir site or storage basin should be traversed with a line containing no greater error in closing than is usually admitted in making surveys of land boundaries. Contour lines should be run throughout the reservoir site at elevations of not more than ten feet apart. The area of the watershed should be determined by a survey such as the necessities of the case may require. As has already been stated, the location of the principal points on the boundaries of the watershed is sometimes sufficient, while at other times the exigencies of the case may require a traverse survey similar to that recommended for obtaining the area of the reservoir site. The topography of the watershed and the length and courses of its main drainage channels should be de termined by appropriate surveys. Cross sections of the canyon or outlet of the valley at the point selected for the dam site at distances of not more than ten feet apart, for a width of not less than an eighth of a mile. Borings to bedrock, or other material, suitable for a dam foundation, should be made across the canyon at the dam site at intervals of about twenty five feet. Surveys should be made to determine in what manner the water can be drained from the foundation of the dam. If the draining can be done by cuts or tunnels the length of these should be measured, and the material through which they will be constructed should be noted. If the draining must be by means of pumps, the heighth to which the water will be pumped, as well as the quantity of water to be raised, should be determined. The gauging of the rainfall and discharges from the watershed already referred to should, of course, be made with great care, and such other observations in regard to evaporation, percolation, etc., as are deemed of value should also be made. When all of these data have been collected by reliable surveys, the calculations necessary to determine the value of a reservoir site and the cost of improving it become an easy matter, and an engineer can proceed to make his report with certainty and confidence. ADULTERATION OF FOOD PRODUCTS. BY W. C. FITZSIMMONS. THE average citizen has little concep tion of the extent to which much of our daily food is adulterated with foreign substances, many of which are injurious to health. A still greater portion of the adulterants used are often, if not always, distasteful or disgusting. A theory of some scientists is that the ultimate atoms of matter are all of the same substance, and that material things as we find them, so varied and diverse in characteristics, are merely the results of an infinite diversity of combinations among the ultimate atoms and molecules of matter. It is asserted that a palatable article of syrup may be made of rags; and while the ultimate analysis of the two might reveal the same primal elements in their composition, the knowledge of the fact would scarcely render such syrup especially appetizing. In order to give readers some conception of the extent to which adulteration of substances daily consumed by all is practiced, citations from a report emanating from the Department of Agriculture will prove of value. It was found by a series of careful and prolonged investigations covering the range of nearly all food products, includ ing potatoes, that the amount of adulteration is at least 15 per cent. of which no less |