Volume 39 (1879) (446 pages)

54 MINING AND SCIENTIFIC PRESS. [July 26, 1879, The Absorption of Hygroscopic Moisture by Cereal Grains. {Graduating Thesis of Epsoxp O’Neitz, College of Agriculture, University of California. ] It is well known that all substances absorb moisture from the air, The effect of this is geen in the swelling and curling of animal and vegetable substauces. This is the principle on which cat-gut and horse hair hygrometers are constructed. The moisture thus attracted, is deposited in an exceediugly thin film, not apparent to the eye or to the touch, Even substances like polished metals and glass are thus covered with an invisible coating of moisture, as is made apparent by weighing the glass, wip ing it with a dry cloth, and again weighing. The second weight is invarially the smaller, owing to the removal of the film. On standing, more moisture is attracted, and it resumes its former weight. The presence of this film may also be shown by writing on the glass with any object. This will remove the film, and, on breathing on the glass, the writing will become apparent, on account of the amount of condensed moisture being less on the places where the film was removed. This phenomenon is often a cause of considerable error in weighing large pieces of apparatus. The cause of this absorption is the physical attraction between the aqueous particles and tbe particles of the substance. If the substance be either porous or capable of entering into cbemical combination with the water, much more will he ahsorbed than in the case of glass, A porous substance, like brick or charcoal, will increase in weight many times more than a piece of glass of the same size, merely on account of the larger surface. Some substances, like nitrate of sodium, or chloride of calcium, will continne to attract moisturé until they form a liquid. Suhstances like sulphuric acid and phosphoric anhydride, which form a chemical combination with the water, will attract every particle of moisture from a limited volume of air, as a new surface, capable of attraction and combination, is always presented, Grains, seed, flour, cloth and even oils, absorb considerable amounts of water. In Europe, valuable substances like silk and wool are always sold with an allowance for contained inoisture. The temperature and humidity of the atmosphere are ohserved, and, by means of tables previously determined hy experiment, the amount of water in the silk obtained, It is often considerable at 55° Fahr., being about 15% (Knop.}. This absorptiou property is of great importance in the case of soils. Davy maintained that the fertility of a soil was proportional to its hygroscopic power. This, however, is not always true. The absorhent power is generally proportional to the porosity or fineness of division. According to Schubler, coarse, silicious sand, exposed to a saturated atmosphere, absorbed nothing in 72 hours; fiue caleareous sand, three-tenth per cent; clay, 8%; and humus, 12%. This shows the etfect of fineness of nivision; but soils containing humus and clay are generally fertile, which explains Davy’s proposition. Tn California, this absorptive power is practically noticeable in the case of the cereal grains, The bulk of these crops are raised in the interior of the State, and generaly stored there for some time. The climate in summer is extraordinarily dry, and the grains will give un nearly every particle of moisture. When removed to San Francisco and stored in damp warehouses, or shipped to a foreign port in the hold of a vessel, where the atmosphere is nearly saturated, the weight is materially increased. It has been said that this additional weight will pay the enere eet of freight from San Francisco to Liverool, This absorbent power has heen noticed very often, especially in California. A writer in the Pacific Rural Press mentions the fact that the lower sacks stored in a warehouse gain a considerable amount. The reason that the lower ones gain more, is that the moisture, which generally comes from below, is almost completely absorbed by these lower layers, none heing left for the upper ones. Another person mentions that the outside sacks of a pile of freshly threshed grain standing in the field for 10 daye weighed 30 pounds less than the inner sacks, Freshly threshed grain always contaius moisture, and it was the loss of this which caused the difference. The time, being only 10 days, was not sufficient to allow the inner layers to dry out. Several other instances have heen noticed and they all agree that the grains may gain or lose a very large amount in a compara. tively short time. As mauy inquiries have been made as to the actual amount vhat could be gaiued or lost, and to whom the profit went, experiments were made to determine these points. It would be very important to the farmer to know whether it would be profitable to store his grain, or to sell it off the field; whether the commission merchant should take the farmer’s weight, or to weigh it himself inSan Francisco, Ali these points are of the greatest practical importance to the grain raisere of the State. The amount of ahsorption may be measured in several ways. Among the oldest and not very accurate ones are those of Leslie. Thesubstance was dried at as high a temperature as possible without changing it, placed in a flask with a small opening, and the whole exposed to a saturated atmosphere. The amount of moisture in the small flask was measured by means of a delicate hygrometer, and this was assumed to be proportional to the amount absorbed by the substance. In this way he obtained the relative absorptive powere of a great many substances, Schubler’s method was to place the substance, previously dried at a temperature of 100°— 200° C., on a small table standing in water, and to’cover the whole with a bell-jar. The increase of weight indicated the amount of water ahsorbed, The defects of this method were, that the layer of substance was too thick, the time of exposure not long enough, and with his appliances the atmosphere not fully saturated. This latter was proved by Knop, who showed that moistened filter paper loses weight when exposed to an atmosphere like that employed by Schubler. ‘The method adopted by me was Schubler’s, as modified by Prof. Hilgard. The bell-jar was made as low as possible, and filter paper, dipping into the water below surrounded the suhstance, which was spread ont in as thin a layer as possible. Even with these precautions, the grain will continue to ahsorb for a period of from 12 to 18 days. Since temperature changed the amount of water in a saturated atmosphere very much, the apparatus was placed in a room where the temperature was constant, about 18”. Experiments according to this method were made with wheat, barley and oats. About 25 grammes of each were employed, spread out on large watch-glasses, The weighings were made in a corked flask, as the grain lost weight rapidly when removed from the apparatue, The ahsorption was accompanied by considerable swelling, which, however, was not measured, The following table shows the percentage of moisture ahsorbed by air-dry substances from a saturated atmosphere, the temneérature being DifferBarDifferDifferOnes ences, ley. ences, TE, ences 3.380 7.79 3.52 7.00 3.26 6.56 5. -56 5.54 54 4.11 AG 1.85 7.00 2.54 0.56 1.5 1.20 7.54 1,70 7.02 1.2 1.00 8.68 1.30 8 00 13 1,00 1.44 1.30 10.05 Loy 07 oon 1.27 anos 1.3 50 14.00 -60 13.05 2.6 34 15.10 -50 14.18 2.5 82 18.32 1.21 17.40 1.2 ve 19.70 1.34 18.79 1.0 60 ona 1.01 anes 1,2 32 20.38 43 oe Pap The differences are for periods of 24 hours each, We see that although the total amounts absorbed by these grains differ slightly, yet they seem to follow the same general law, 7% ¢., a gradual increase, at first very rapid and then slowly becoming less until about the 13th or 14th day, when a sudden increase occurs. This is due to the development of mold owing to the great amount of moisture present. Nearly half the total increase occure in the lirst 24 hours, and most of it in the lrst part of this time, as shown below. Difference between grains during the first 24 hours: Shours. 15 hours. 24 hours, 14 days. Odts veneers 3.80 1:20 2,79 10:1 Barley. oeey 2.02 1.46 12.7 WIECH nonmoonsann 3.26 St 2.45 14.23 In the second 24 bours scarcely anything was absorbed. This was probably due to a sudden change of temperature. Experiments were also made to determine the amount of water in the air-dry graine. They were exposed to a perfectly dry atmosphere at 18°. The apparatus employed was a common sulphuric acid dessicator. The grains, especially the wheat, shrank very much and became hard and bony. The results were as follows. The table of differences as before refer to periods of 24 hours: Percentage of water lost by air-dry grain exposed to absolutely dry atmosphere at 18° C.: DifferBarDifferDifferCats. enees, ley. ences. Wheat. “cnees, 2 d’ys.4.45 3.00 8.39 2.00) 8.11 2.00 . 145 1.39 } 1.11 i 3 d’ys.5.67 io 4.41 1,02 i 4.18 1.07 4 8 A5 4 d’ys.6.53 “iat 5.20 oh } 4,63 235 Ee . 20 5 d'ys.6.05 au 5.51 223 4.98 1 . 24 07 6 d’ys.7.43 a 5.86 a v 5.00 05 . 215 03) 7 d’ys.7.99 oe 6.14 20 5.12 28 . oly) 05 9 d’ys.7.14 ar 6.55 Bs 5.18 20 . al 18 Tl d'ys.8.53 ah 6.96 12 5.46 “ist a: 10 Be: 12 d’ys.8.69 .09 7.18 .09 5.51 01 18 d'ys.9.32 on 7.79 meee 6.23 . There is a gradual decrease, more rapid at first, as seen by the column of differences, About half is lost in the first two days. According to the above determination, perfectly dry grain, exposed to a saturated atmosphere, will absorb the following amounts, at a temperature of 18° C.: (Us Bioouosbudecd MWuN ce dbonboonnsoonrooneannd + 29.087 Barle 23.174 Wheat, ponG cuore OL ORE ie ane 25.027 ‘Wheat is thus seen to be less hygroscopic than oats or barley. Perhaps this is owit chaff of the ie ia Say? ae As the temperature of the interior of the State in summer is about 80° F., the experiment of drying the wheat at this temperature was tried. The grain was placed in a flask, which was kept at a temperature of 30° C., by means of a water bath, and dry air passed over. The results were as follows: TemperTime of Percent. ature. exposure, lost. ELSE C Sete sterstettee ste tstatieeterstete sta 18 days=432 hrs. 6.23 Billet Orica cama dcnadannsndses 30 hrs. 7.65 This shows that an increase of temperature increases the amount of moisture lost and decreases the time. According to Knop, wheat, dried at 120°, loses 14.6% of water. The air even in the interior is never fully saturated, According to Logan the .average dew point of the Sacramento valley in summer is 50, the temperature being about 70°F. This shows that the air contains 39.39% of moisture. The annual average dew point is 48, the temperature heing 61° F. This corresponds to 52% of moisture. Experiments were made with air of this degree of situation. This was done by means of a solution of chloride of calcium. According to Gay Lussac the tension of aqueous vapor formed by a solution of chloride of calcium of the specific gravity 1.343 at 10° C., has a tension of 50.5, the tension of aqueous vapor in a saturated atmosphere being taken at 100, In other words the air above euch a solution is half saturated, Since a eolution at 180° (the temperature used) is less dense than at 10°, a correction must be made. It was assumed to decrease in the same ratio ae water, and, therefore, a solution of specific gravity 1.3418 was employed. Wheat was placed over this and surrounded by filter paper as before. The amount absorbed by wheat dried at 30° C., from a saturated atmosphere and from a half saturated one, is ehown below. pont absorbed in 12 days, temperature + San Luis Park, Colorado. From Goy. Gilpin’s article in the Colorado Miner we learn that the San Luis park is an immense elliptical bowl, the bed of a primeval sea which has been drained; its bottom, smooth as a water surface aud concave, ie 9,400 square miles in area. It is watered by 35 mountain streams, which, descending from the encircling crest of snow, converge, 19 into the San Luis lake, the rest into the Rio del Norte. An extraordinary symmetry of configuration is its prominent feature, The scenery, everywhere sublime, has the ever-changing variety of the kaleidoscope. Entirely around the edge of the plain, and closing the*junction of the plain with the monntain’s foot, runs a smooth glasis, exactly resembling the sea beach, which accompanies the coujunction of the land with the ocean, From this beach rise continuously all around the horizon the great mountains, elevating their heads above the line of perpetual snow, On the eastern side the escarpment of the Cordilleras rises rapidly, and is abrupt; on the western side the crest of the Sierra Mimbres is more remote, having the interval filled with ridges, lessening in altitude as they descend to the plain of the park. This continuous shelving flank of the Sierras completing a perfect amphitheater, has a euperficial area equal to that of the plain which it envelops, and gives to the whole enclosure within the encircling band of snow an area of 18,000 square miles, At an elevation of 5,000 or 6,000 feet above the plain a level line upon the mountain wall marks the cessation of arborescence, Above solution of Chloride of Calcium... 3.40% . and above which naked granite and snow alone (OE WAKET ieee etree cee ene neon eee 22.9 %]are eeen. To one who ascends to this elevation This result shows that half saturated air acts almost like dried air, and, therefore, that wheat from the Sacramento valley may be considered as being almost absolutely dry, and hence capable of taking up 20% or more of moisture. We can now see what an important factor this absorption of moisture is in the case of grains. The great bulk of our wheat may be considered as dry during the summer, aud on transportation to a damper climatemay possibly increase 25%, and again of 5% to 15% may be looked for with almost absolute certainty. This is clear prolit, and might just as well be appropriated by our farmers as by the commission merchants or foreign dealers. Further experiments are necessary to determine the amount of moisture in newly threshed grain, and the rapidity with which it is lost when stored in the field and warehouses during summer; the effect of one-quarter, threequarters or other intermediate degrees of saturation; the influence of large and small piles; and whether the difference of absorption of different grains is not due to the chaff. The determination of these points and also the degree of saturation of the air of the warehouses of San Francisco and large grain regions, will enable us to estimate the amount of moisture absorbed by the cereal grains very accurately. The Age of Wonders. A recent English writer, reviewing the scientific and industrial achievements of the past balf century, calls this ‘‘the age of wonders,” and refers as follows to a few out of the many modern marvels that fully justify the appellation: We have seen a substancé which our ancestors proudly used to obliterate a pencil mark so molded to our use as to make man almost an amphihious animal; a noxious vapor, from which they would turn with disgust, made the means of a brilliant light, which enahles the night almost to rival the day. We have seen the surgeon’s knife, to them an instrument of necessary torture, divested of its horror by a discovery which gives a temporary insensibility to pain, which enablee the euffering patient to wake from nothing more than a troubled dream, and find that over, under which, withont this, his fortitnde might have faltered, or his constitution sunk. We have seen a power which is inexhaustible eo long as the elements of fire and water remain, the effects of which our grandmothers may have witnessed with a sigh, when terminating, by a sudden crash, the serene music of their tea-kettles; but which, by the combined efforts of modern science, has become the very hands and feet of the world, the great and almost universal manufacturer-for man; the great propeller by which we rival the flight of the bird, and which so unites the human family that degrees of latitude and longitude are little more than milestones on the great highway of the world. And, lastly, we have seen that subtle power which our ancestors recognized only in the minute spark of the electric circle transformed into the faithful, untiring agent of the human mind, bearing its thoughts from one end ofa vast continent to the other with an accuracy which would be in vain looked for in any other messenger, and with a speed which far outstrips the action of the mind which formed them. ‘Quick as thought” will not do now to express the greatest speed, and ‘“‘quick as lightning” has become a practical, not merely a figurative expression. From March 8th to July 7th, $25,231 in gold was received froma private gravel claim at lowa Hill, Placer county. This claimis owned and worked hy a retired merchant of San Francisco, and ie only a single illustration of what a little capital, judiciously invested in gravel claims, will accomplish. from any point, the whole interior of this prodigious amphitheater, displaying an elliptical arc of 11,520,000 acres, is scanned by the eye and swept in at a eingle glance. Aided by a glass, the smallest objects scattered over the immense elliptical area beneath are discernible throngh the limpid, brilliant and translucent atmosphere, Two facts impress tbhemselvee upon the senses; the perfect eymmetry of configuration in uature, and the intense variety in the form and splendor of the landscape. The average elevation of the plain above tbe sea level is 6,400 feet. The highest peaks have an altitude of 16,000 feet above the sea, In tbe serrated rim of the park, as seen from the plain projected against the canopy, are discernible 17 peaks, at very eqnal distances from one another. Each one differs from all the rest in some peculiarity of shape and position. The park is an immense elliptical basin enveloping the sources of the Rio del Norte. It is isolated in the heart of the continent, 1,200 miles from any sea. It is mortised, as it were, in the midst of the vast mountain bulk, where, rising gradually from the oceans, the bighest altitude and amplitude of the continent is attained. This park spreads its plain from 36° to 38° 30’, and is hisected by the 106th meridian. Its greatest length is 210 miles; its greatest width is 100 miles; its aggregate approximate area is 10,000 square miles. The comb of the Sierra, surrounding this im-mense bowl, presents the prodigious plates of primeval porphyry driven up, as the subsoil of a furrow, from the lowest terrestrial crust and protruding their vertical edges toward the sky. The summit, yielding to the corroding forces, presents a wedge towards the canopy, is arranged in peaks resembling the teeth of a saw, is above all arborescence, and is either clad in perpetual snow or ie bald rock. Against this is lapped perpendicularly the second stratum, less by many thousand feet in altitude, its top forming a rim or bench, This bench, being the rended ridge of the erupted stratum, softer than the first and receiving the debris from above, has a deep fertile soil, a luxuriant alpine vegetation, forests of fir, and is the highest region of arborescence and vegetable ‘owth. This is the region of rocks, where the metals, especially gold and silver, abound in crevicee charged and infused with the richest ores. It is from hence that the gold of the gulches ie disintegrated and descends, Here are springs of water and the sourcesof rivers, The timber is excellent, and the pastures of various grasses luxnriant and inexhaustible. Swept by the ascending currents of vapor, irrigation is conetant. This elevated bench is a permanent characteristic of the mountain flank, continuous as the continent itself; a colossal staircase, whose steps are themselves of mountain magnitude. The enveloping Sierras, which hoop in the park in an unbroken circuit, have 1,000 miles of length. The cloud compelling crests, throughout and continuously, reaches and ascends into the region of perpetual snow. The veins of gold and silver-bearing rocks average all along 10,500 feet in altitude. They have a like continuous and nndeviating length and circuit, These veins are crossed and scored by 100 and more considerable etreams, descending through them from the snows above. These all concentrate into the bowl of the park beneath. The channels, their confluent waters, and the sands from the full-veined mountains flanks, are here stopped and accumulate, The abrasions, going on during countless centuries, are here concentrated; they are gathered and remain npon the bedrock underlying the abraded dehris. The profound and subtile scrutiny given by Humboldt to the South American Andes is systemized in volume V. of Cosmos under the definition: ‘‘The reaction of the interior of the a

54 MINING AND SCIENTIFIC PRESS. [July 26, 1879, The Absorption of Hygroscopic Moisture by Cereal Grains. {Graduating Thesis of Epsoxp O’Neitz, College of Agriculture, University of California. ] It is well known that all substances absorb moisture from the air, The effect of this is geen in the swelling and curling of animal and vegetable substauces. This is the principle on which cat-gut and horse hair hygrometers are constructed. The moisture thus attracted, is deposited in an exceediugly thin film, not apparent to the eye or to the touch, Even substances like polished metals and glass are thus covered with an invisible coating of moisture, as is made apparent by weighing the glass, wip ing it with a dry cloth, and again weighing. The second weight is invarially the smaller, owing to the removal of the film. On standing, more moisture is attracted, and it resumes its former weight. The presence of this film may also be shown by writing on the glass with any object. This will remove the film, and, on breathing on the glass, the writing will become apparent, on account of the amount of condensed moisture being less on the places where the film was removed. This phenomenon is often a cause of considerable error in weighing large pieces of apparatus. The cause of this absorption is the physical attraction between the aqueous particles and tbe particles of the substance. If the substance be either porous or capable of entering into cbemical combination with the water, much more will he ahsorbed than in the case of glass, A porous substance, like brick or charcoal, will increase in weight many times more than a piece of glass of the same size, merely on account of the larger surface. Some substances, like nitrate of sodium, or chloride of calcium, will continne to attract moisturé until they form a liquid. Suhstances like sulphuric acid and phosphoric anhydride, which form a chemical combination with the water, will attract every particle of moisture from a limited volume of air, as a new surface, capable of attraction and combination, is always presented, Grains, seed, flour, cloth and even oils, absorb considerable amounts of water. In Europe, valuable substances like silk and wool are always sold with an allowance for contained inoisture. The temperature and humidity of the atmosphere are ohserved, and, by means of tables previously determined hy experiment, the amount of water in the silk obtained, It is often considerable at 55° Fahr., being about 15% (Knop.}. This absorptiou property is of great importance in the case of soils. Davy maintained that the fertility of a soil was proportional to its hygroscopic power. This, however, is not always true. The absorhent power is generally proportional to the porosity or fineness of division. According to Schubler, coarse, silicious sand, exposed to a saturated atmosphere, absorbed nothing in 72 hours; fiue caleareous sand, three-tenth per cent; clay, 8%; and humus, 12%. This shows the etfect of fineness of nivision; but soils containing humus and clay are generally fertile, which explains Davy’s proposition. Tn California, this absorptive power is practically noticeable in the case of the cereal grains, The bulk of these crops are raised in the interior of the State, and generaly stored there for some time. The climate in summer is extraordinarily dry, and the grains will give un nearly every particle of moisture. When removed to San Francisco and stored in damp warehouses, or shipped to a foreign port in the hold of a vessel, where the atmosphere is nearly saturated, the weight is materially increased. It has been said that this additional weight will pay the enere eet of freight from San Francisco to Liverool, This absorbent power has heen noticed very often, especially in California. A writer in the Pacific Rural Press mentions the fact that the lower sacks stored in a warehouse gain a considerable amount. The reason that the lower ones gain more, is that the moisture, which generally comes from below, is almost completely absorbed by these lower layers, none heing left for the upper ones. Another person mentions that the outside sacks of a pile of freshly threshed grain standing in the field for 10 daye weighed 30 pounds less than the inner sacks, Freshly threshed grain always contaius moisture, and it was the loss of this which caused the difference. The time, being only 10 days, was not sufficient to allow the inner layers to dry out. Several other instances have heen noticed and they all agree that the grains may gain or lose a very large amount in a compara. tively short time. As mauy inquiries have been made as to the actual amount vhat could be gaiued or lost, and to whom the profit went, experiments were made to determine these points. It would be very important to the farmer to know whether it would be profitable to store his grain, or to sell it off the field; whether the commission merchant should take the farmer’s weight, or to weigh it himself inSan Francisco, Ali these points are of the greatest practical importance to the grain raisere of the State. The amount of ahsorption may be measured in several ways. Among the oldest and not very accurate ones are those of Leslie. Thesubstance was dried at as high a temperature as possible without changing it, placed in a flask with a small opening, and the whole exposed to a saturated atmosphere. The amount of moisture in the small flask was measured by means of a delicate hygrometer, and this was assumed to be proportional to the amount absorbed by the substance. In this way he obtained the relative absorptive powere of a great many substances, Schubler’s method was to place the substance, previously dried at a temperature of 100°— 200° C., on a small table standing in water, and to’cover the whole with a bell-jar. The increase of weight indicated the amount of water ahsorbed, The defects of this method were, that the layer of substance was too thick, the time of exposure not long enough, and with his appliances the atmosphere not fully saturated. This latter was proved by Knop, who showed that moistened filter paper loses weight when exposed to an atmosphere like that employed by Schubler. ‘The method adopted by me was Schubler’s, as modified by Prof. Hilgard. The bell-jar was made as low as possible, and filter paper, dipping into the water below surrounded the suhstance, which was spread ont in as thin a layer as possible. Even with these precautions, the grain will continue to ahsorb for a period of from 12 to 18 days. Since temperature changed the amount of water in a saturated atmosphere very much, the apparatus was placed in a room where the temperature was constant, about 18”. Experiments according to this method were made with wheat, barley and oats. About 25 grammes of each were employed, spread out on large watch-glasses, The weighings were made in a corked flask, as the grain lost weight rapidly when removed from the apparatue, The ahsorption was accompanied by considerable swelling, which, however, was not measured, The following table shows the percentage of moisture ahsorbed by air-dry substances from a saturated atmosphere, the temneérature being DifferBarDifferDifferOnes ences, ley. ences, TE, ences 3.380 7.79 3.52 7.00 3.26 6.56 5. -56 5.54 54 4.11 AG 1.85 7.00 2.54 0.56 1.5 1.20 7.54 1,70 7.02 1.2 1.00 8.68 1.30 8 00 13 1,00 1.44 1.30 10.05 Loy 07 oon 1.27 anos 1.3 50 14.00 -60 13.05 2.6 34 15.10 -50 14.18 2.5 82 18.32 1.21 17.40 1.2 ve 19.70 1.34 18.79 1.0 60 ona 1.01 anes 1,2 32 20.38 43 oe Pap The differences are for periods of 24 hours each, We see that although the total amounts absorbed by these grains differ slightly, yet they seem to follow the same general law, 7% ¢., a gradual increase, at first very rapid and then slowly becoming less until about the 13th or 14th day, when a sudden increase occurs. This is due to the development of mold owing to the great amount of moisture present. Nearly half the total increase occure in the lirst 24 hours, and most of it in the lrst part of this time, as shown below. Difference between grains during the first 24 hours: Shours. 15 hours. 24 hours, 14 days. Odts veneers 3.80 1:20 2,79 10:1 Barley. oeey 2.02 1.46 12.7 WIECH nonmoonsann 3.26 St 2.45 14.23 In the second 24 bours scarcely anything was absorbed. This was probably due to a sudden change of temperature. Experiments were also made to determine the amount of water in the air-dry graine. They were exposed to a perfectly dry atmosphere at 18°. The apparatus employed was a common sulphuric acid dessicator. The grains, especially the wheat, shrank very much and became hard and bony. The results were as follows. The table of differences as before refer to periods of 24 hours: Percentage of water lost by air-dry grain exposed to absolutely dry atmosphere at 18° C.: DifferBarDifferDifferCats. enees, ley. ences. Wheat. “cnees, 2 d’ys.4.45 3.00 8.39 2.00) 8.11 2.00 . 145 1.39 } 1.11 i 3 d’ys.5.67 io 4.41 1,02 i 4.18 1.07 4 8 A5 4 d’ys.6.53 “iat 5.20 oh } 4,63 235 Ee . 20 5 d'ys.6.05 au 5.51 223 4.98 1 . 24 07 6 d’ys.7.43 a 5.86 a v 5.00 05 . 215 03) 7 d’ys.7.99 oe 6.14 20 5.12 28 . oly) 05 9 d’ys.7.14 ar 6.55 Bs 5.18 20 . al 18 Tl d'ys.8.53 ah 6.96 12 5.46 “ist a: 10 Be: 12 d’ys.8.69 .09 7.18 .09 5.51 01 18 d'ys.9.32 on 7.79 meee 6.23 . There is a gradual decrease, more rapid at first, as seen by the column of differences, About half is lost in the first two days. According to the above determination, perfectly dry grain, exposed to a saturated atmosphere, will absorb the following amounts, at a temperature of 18° C.: (Us Bioouosbudecd MWuN ce dbonboonnsoonrooneannd + 29.087 Barle 23.174 Wheat, ponG cuore OL ORE ie ane 25.027

‘Wheat is thus seen to be less hygroscopic than oats or barley. Perhaps this is owit chaff of the ie ia Say? ae As the temperature of the interior of the State in summer is about 80° F., the experiment of drying the wheat at this temperature was tried. The grain was placed in a flask, which was kept at a temperature of 30° C., by means of a water bath, and dry air passed over. The results were as follows: TemperTime of Percent. ature. exposure, lost. ELSE C Sete sterstettee ste tstatieeterstete sta 18 days=432 hrs. 6.23 Billet Orica cama dcnadannsndses 30 hrs. 7.65 This shows that an increase of temperature increases the amount of moisture lost and decreases the time. According to Knop, wheat, dried at 120°, loses 14.6% of water. The air even in the interior is never fully saturated, According to Logan the .average dew point of the Sacramento valley in summer is 50, the temperature being about 70°F. This shows that the air contains 39.39% of moisture. The annual average dew point is 48, the temperature heing 61° F. This corresponds to 52% of moisture. Experiments were made with air of this degree of situation. This was done by means of a solution of chloride of calcium. According to Gay Lussac the tension of aqueous vapor formed by a solution of chloride of calcium of the specific gravity 1.343 at 10° C., has a tension of 50.5, the tension of aqueous vapor in a saturated atmosphere being taken at 100, In other words the air above euch a solution is half saturated, Since a eolution at 180° (the temperature used) is less dense than at 10°, a correction must be made. It was assumed to decrease in the same ratio ae water, and, therefore, a solution of specific gravity 1.3418 was employed. Wheat was placed over this and surrounded by filter paper as before. The amount absorbed by wheat dried at 30° C., from a saturated atmosphere and from a half saturated one, is ehown below. pont absorbed in 12 days, temperature + San Luis Park, Colorado. From Goy. Gilpin’s article in the Colorado Miner we learn that the San Luis park is an immense elliptical bowl, the bed of a primeval sea which has been drained; its bottom, smooth as a water surface aud concave, ie 9,400 square miles in area. It is watered by 35 mountain streams, which, descending from the encircling crest of snow, converge, 19 into the San Luis lake, the rest into the Rio del Norte. An extraordinary symmetry of configuration is its prominent feature, The scenery, everywhere sublime, has the ever-changing variety of the kaleidoscope. Entirely around the edge of the plain, and closing the*junction of the plain with the monntain’s foot, runs a smooth glasis, exactly resembling the sea beach, which accompanies the coujunction of the land with the ocean, From this beach rise continuously all around the horizon the great mountains, elevating their heads above the line of perpetual snow, On the eastern side the escarpment of the Cordilleras rises rapidly, and is abrupt; on the western side the crest of the Sierra Mimbres is more remote, having the interval filled with ridges, lessening in altitude as they descend to the plain of the park. This continuous shelving flank of the Sierras completing a perfect amphitheater, has a euperficial area equal to that of the plain which it envelops, and gives to the whole enclosure within the encircling band of snow an area of 18,000 square miles, At an elevation of 5,000 or 6,000 feet above the plain a level line upon the mountain wall marks the cessation of arborescence, Above solution of Chloride of Calcium...... 3.40% . and above which naked granite and snow alone (OE WAKET ieee etree cee ene neon eee 22.9 %]are eeen. To one who ascends to this elevation This result shows that half saturated air acts almost like dried air, and, therefore, that wheat from the Sacramento valley may be considered as being almost absolutely dry, and hence capable of taking up 20% or more of moisture. We can now see what an important factor this absorption of moisture is in the case of grains. The great bulk of our wheat may be considered as dry during the summer, aud on transportation to a damper climatemay possibly increase 25%, and again of 5% to 15% may be looked for with almost absolute certainty. This is clear prolit, and might just as well be appropriated by our farmers as by the commission merchants or foreign dealers. Further experiments are necessary to determine the amount of moisture in newly threshed grain, and the rapidity with which it is lost when stored in the field and warehouses during summer; the effect of one-quarter, threequarters or other intermediate degrees of saturation; the influence of large and small piles; and whether the difference of absorption of different grains is not due to the chaff. The determination of these points and also the degree of saturation of the air of the warehouses of San Francisco and large grain regions, will enable us to estimate the amount of moisture absorbed by the cereal grains very accurately. The Age of Wonders. A recent English writer, reviewing the scientific and industrial achievements of the past balf century, calls this ‘‘the age of wonders,” and refers as follows to a few out of the many modern marvels that fully justify the appellation: We have seen a substancé which our ancestors proudly used to obliterate a pencil mark so molded to our use as to make man almost an amphihious animal; a noxious vapor, from which they would turn with disgust, made the means of a brilliant light, which enahles the night almost to rival the day. We have seen the surgeon’s knife, to them an instrument of necessary torture, divested of its horror by a discovery which gives a temporary insensibility to pain, which enablee the euffering patient to wake from nothing more than a troubled dream, and find that over, under which, withont this, his fortitnde might have faltered, or his constitution sunk. We have seen a power which is inexhaustible eo long as the elements of fire and water remain, the effects of which our grandmothers may have witnessed with a sigh, when terminating, by a sudden crash, the serene music of their tea-kettles; but which, by the combined efforts of modern science, has become the very hands and feet of the world, the great and almost universal manufacturer-for man; the great propeller by which we rival the flight of the bird, and which so unites the human family that degrees of latitude and longitude are little more than milestones on the great highway of the world. And, lastly, we have seen that subtle power which our ancestors recognized only in the minute spark of the electric circle transformed into the faithful, untiring agent of the human mind, bearing its thoughts from one end ofa vast continent to the other with an accuracy which would be in vain looked for in any other messenger, and with a speed which far outstrips the action of the mind which formed them. ‘Quick as thought” will not do now to express the greatest speed, and ‘“‘quick as lightning” has become a practical, not merely a figurative expression. From March 8th to July 7th, $25,231 in gold was received froma private gravel claim at lowa Hill, Placer county. This claimis owned and worked hy a retired merchant of San Francisco, and ie only a single illustration of what a little capital, judiciously invested in gravel claims, will accomplish. from any point, the whole interior of this prodigious amphitheater, displaying an elliptical arc of 11,520,000 acres, is scanned by the eye and swept in at a eingle glance. Aided by a glass, the smallest objects scattered over the immense elliptical area beneath are discernible throngh the limpid, brilliant and translucent atmosphere, Two facts impress tbhemselvee upon the senses; the perfect eymmetry of configuration in uature, and the intense variety in the form and splendor of the landscape. The average elevation of the plain above tbe sea level is 6,400 feet. The highest peaks have an altitude of 16,000 feet above the sea, In tbe serrated rim of the park, as seen from the plain projected against the canopy, are discernible 17 peaks, at very eqnal distances from one another. Each one differs from all the rest in some peculiarity of shape and position. The park is an immense elliptical basin enveloping the sources of the Rio del Norte. It is isolated in the heart of the continent, 1,200 miles from any sea. It is mortised, as it were, in the midst of the vast mountain bulk, where, rising gradually from the oceans, the bighest altitude and amplitude of the continent is attained. This park spreads its plain from 36° to 38° 30’, and is hisected by the 106th meridian. Its greatest length is 210 miles; its greatest width is 100 miles; its aggregate approximate area is 10,000 square miles. The comb of the Sierra, surrounding this im-mense bowl, presents the prodigious plates of primeval porphyry driven up, as the subsoil of a furrow, from the lowest terrestrial crust and protruding their vertical edges toward the sky. The summit, yielding to the corroding forces, presents a wedge towards the canopy, is arranged in peaks resembling the teeth of a saw, is above all arborescence, and is either clad in perpetual snow or ie bald rock. Against this is lapped perpendicularly the second stratum, less by many thousand feet in altitude, its top forming a rim or bench, This bench, being the rended ridge of the erupted stratum, softer than the first and receiving the debris from above, has a deep fertile soil, a luxuriant alpine vegetation, forests of fir, and is the highest region of arborescence and vegetable ‘owth. This is the region of rocks, where the metals, especially gold and silver, abound in crevicee charged and infused with the richest ores. It is from hence that the gold of the gulches ie disintegrated and descends, Here are springs of water and the sourcesof rivers, The timber is excellent, and the pastures of various grasses luxnriant and inexhaustible. Swept by the ascending currents of vapor, irrigation is conetant. This elevated bench is a permanent characteristic of the mountain flank, continuous as the continent itself; a colossal staircase, whose steps are themselves of mountain magnitude. The enveloping Sierras, which hoop in the park in an unbroken circuit, have 1,000 miles of length. The cloud compelling crests, throughout and continuously, reaches and ascends into the region of perpetual snow. The veins of gold and silver-bearing rocks average all along 10,500 feet in altitude. They have a like continuous and nndeviating length and circuit, These veins are crossed and scored by 100 and more considerable etreams, descending through them from the snows above. These all concentrate into the bowl of the park beneath. The channels, their confluent waters, and the sands from the full-veined mountains flanks, are here stopped and accumulate, The abrasions, going on during countless centuries, are here concentrated; they are gathered and remain npon the bedrock underlying the abraded dehris. The profound and subtile scrutiny given by Humboldt to the South American Andes is systemized in volume V. of Cosmos under the definition: ‘‘The reaction of the interior of the a