Exploiting lattice potentials for sorting chiral particles

Several ways are demonstrated of how periodic potentials can be exploited for sorting molecules or other small objects which only differ by their chirality. With the help of a static bias force, the two chiral partners can be made to move along orthogonal directions. Time-periodic external forces even lead to motion into exactly opposite directions.Comment: 4 pages, 4 figure

Experiments with potatoes in 1889-1890

It is more difficult to improve the potato, (Solanum tuberosum) by the production of new varieties from seeds, than any other common field or garden vegetable. Although hundreds of promising kinds are produced every year, yet none of the new varieties is better than the old Mercer, Pink Eye, Snow Flake, Early Goodrich or Jersey Peach-blow. No other experiments have been tried oftener, than the planting of big potatoes against little ones or pieces with several eyes or single eyes, yet nothing has been gained by such experiments. Sometimes the little potatoes or the single eyes come out ahead; but generally, about the time that the results appear to be satisfactory, somebody else gets very different results. I have conducted such experiments and many others, without being able to discover why potatoes are inclined to degenerate, or why the single eye pieces come out ahead one year and fall behind the next. In 1888, we planted about 80 varieties of potatoes on our experiment grounds. All of the seed potatoes had been carefully assorted, and they were cut into two and three-eyed pieces as nearly alike in size as possible. The planting of all of the varieties was done on the 21st day of May in the same manner, and they received the same cultivation during the following summer. About the time the early varieties were flowering, I observed that all of the stalks or vines of certain kinds were of the same size and equally vigorous, and that there were great differences between the vines of other varieties. In some of the rows I found the vines of one-third of the hills very vigorous; another third was much less thrifty, and the remaining third were small and appeared to be unhealthy. When we dug the potatoes in the fall, I found as great differences between the products of the hills of the different varieties, as I had found between the vines while they were growing. I was convinced that the discovery of the causes of such differences would show that all of the faults were in the pieces of seed potatoes, and I determined to give the matter special attention during the following summer. About the 1st of May, ’89, I examined our seed potatoes which had been stored in bushel boxes in an out-door cellar, and found that the early varieties had produced sprouts from their seed ends from two to three inches long; but all of the eyes or buds on their stem ends were dormant. I had observed the early sprouting of the seed ends of potatoes often before, and I knew that the terminal buds of trees always started first, and that their stems grew upwards and their roots downwards; but I did not inquire for causes, as I supposed it was their nature to do so. Before leaving the cellar, the question occurred to me: If I should plant the vigorous buds from the seed ends of the potatoes, would they produce a better or a worse crop, than weak and dormant buds from their stem ends? I knew that both ends of the potatoes were well supplied with starch; but I thought that the difference between the starting of the eyes might be caused by a scarcity of albuminoids in their stem ends

Sugar experiments

The United States imports $120,000,000 worth of sugar annually from foreign countries. As we have a great diversity of climate and 110 other country has better soils, it is remarkable that greater efforts have not been made to produce it at home and prevent our money from going abroad. Sugar cane is the only plant from which sugar was made in considerable quantities in this country prior to last year, and it can be grown profitably only within limited areas of Louisiana and Texas. But the results of the experiments which were made with sorghum last year and this year, indicate that skill and suitable machinery is all that is needed to make sugar from it profitably in Kansas and other western states. Since the introduction of Amber cane, only ordinary care has been necessary to produce good syrup cheaply in Iowa, which has generally shown a strong tendency to granulate. This variety of sorghum has proved to be one of our most reliable crops and rich in sucrose; but it is generally understood that sugar can not be extracted from it profitably, except by the use very costly machinery in large factories. I f such belief is well founded, then sugar can not be made in large quantities in Iowa, because the time (twenty to thirty days) is too short between the ripening of the canes and frost, to warrant the expenditure of very large sums of money in sugar factories. But such work can be done as well in small factories as large ones, and that others may judge whether I am right or not, I will explain the principle troubles which are always encountered in making sugar from sorghum and sugar cane. Sucrose is cane sugar, which crystallizes readily when surrounded by favorable conditions, and glucose is grape sugar, which can not be crystallized by the ordinary processes for making sugar

Higher loop corrections to a Schwinger--Dyson equation

We consider the effects of higherloop corrections to a Schwinger--Dyson equations for propagators. This is made possible by the efficiency of the methods we developed in preceding works, still using the supersymmetric Wess--Zumino model as a laboratory. We obtain the dominant contributions of the three and four loop primitive divergences at high order in perturbation theory, without the need for their full evaluations. Our main conclusion is that the asymptotic behavior of the perturbative series of the renormalization function remains unchanged, and we conjecture that this will remain the case for all finite order corrections.Comment: 12 pages, 2 imbedded TiKZ pictures. A few clarifications matching the published versio

Our rusted and blighted wheat, oats and barley in 1890

In 1888 we sowed many kinds of oats, wheat, and barley, but all of them were so much injured by rust, that they were scarcely worth harvesting. In 1889 we sowed them again, and a considerable number of them proved productive, and showed no signs of disease; while others suffered severely from rust, although the growing season was much more favorable for such crops than the preceding one. In 1890 we discarded certain varieties which had proved unreliable and procured others that were promising. On the 26th day of last March, the following kinds of oats were sown broadcast on ground which had produced eighty bushels of shelled corn per acre in 1889, viz: Hargett’s White Seizure, Carter’s Prize Cluster, Station Prize Cluster, Pringle’s Progress, Prince Edward’s Island, American Beauty, Everett’s Scottish Chief, Black Russian, White Russian, Black Prolific, Black Tartarian, Salzer’s White Wonder, White Australian, American Banner, Wide Awake, Race Horse, Badger Queen, White Victoria, Henderson’s Clydesdale, White Bonanza, Centennial, Currie’s Prize Cluster, Welcome, Wilson’s Prolific side oats, Baltic Oats, Giant Yellow French, Lackawana, Golden Giant side oats, Everett side oats, and Improved American Oats. The ground was divided into six long plats by lines running from the east end of the field towards the west, and the plats were numbered from the north to the south side as follow s : 1, 2, 3, 4, 5, and 6. All of the plats were plowed six inches deep, except plat 3 which was not plowed at all. The plowing of plats, 1, 5 and 6 was done in the fall o f 1889, and plats 2 and 4 were plowed on the 25th day of last March. No crops had ever been grown on plat

A feeding experiment

Several years ago I saw an interesting account of a feeding experiment in a newspaper, but the result was not satisfactory. The statement was as follows: “Two fat steers which had been off feed for twelve hours, were fed good rations of corn meal in the morning, and as soon as it was eaten, they were driven across the street to a slaughter house and butchered. When their stomachs were examined, it was found that most of the meal had passed directly from their gullets to the third apartments or manifolds of their stomachs,” but here the experiment was dropped. Dr. Armsby says in his work on cattle feeding, “that cows have been wintered on corn meal exclusively, and that, although rumination was entirely suspended for several months, no ill effects were observed.” As many farmers feed meal and grain to their cows before they give them hay, it is important that we should know whether the remastication of such food is advantageous or not. When we feed meal in large quantities to fattening cattle, much of it passes through them undigested. By mixing meal with cut hay or straw, we could compel cattle to remasticate a large share of it. Would it pay to do so or not, is a question which I tried to solve in February and March of 1889. From a lot of twenty-nine calves, I selected six animals that were from 9 to 10 months old, and much alike in size and vigor. On the eighth day of February, three of them were placed in one stall and the other three in another. On the first day of the trial each lot o f calves received ten pounds of corn and cob meal in the morning and as much more in the evening, and both lots received all of the hay and water that they wanted from the beginning to the end of the experiment. In the west stall the meal was fed dry and timothy hay was fed afterwards. We ran a part of the hay for the lot in the east stall through a feed cutter, and at the regular feeding times some of it was moistened and the rations of meal were thorouglv mixed with it before they were given to the calves. In a few days the daily allowance of meal for each lot of calves was increased from twenty to twenty-four pounds, which was the daily meal ration afterwards to the end of the trial. After the 12th o f March, each lot of calves received daily seven pounds of beets. The weight of each calf was recorded daily from the beginning to the end o f the experiment

Experiments in making and storing hay

The report of the U. S. Department of Agricuture fo 1889 shows that 3,600,000 acres of grass was cut for hay in Iowa in 1888. If the average yield was 1% tons of hay per acre, then the product of the state was 4,500.000 tons, which (at $4.00 per ton,) was worth$18,000,000. By general observation and from my own experience in feeding hay, I know that more than one-third of the value of each of our hay crops is lost on account of late cutting; exposure to rains, dews and the sun, and avoidable injuries after being stacked or stored in barns. If such great losses as that of $9,000,000 on our hay crop in 1888 were unusual, it would not be remarkable if we should give them but little attention; but as they are common annual losses, it is strange that greater efforts are not made to prevent them. I made from ninety to one-hundred tons of timothy and clover hay annually on my farm in Black Hawk county for twenty years; but I have learned long ago, that it is very difficult to cure grasses properly in Iowa when they are in the best condition for hay on account of unfavorable weather. It is but seldom that we do not have showers of rain; a very damp atmosphere; wet meadows, or heavy dews during haying times, which cause great losses even when good judgment and great care is used in performing the work. Many farmers begin to make hay at the proper time; but they let the work drag along until the greater part of their grass is ripe before it is cut. Others wait until their timothy and clover is ripe; because such grass is most easily cured, or because hay which is made from ripe grass is generally free from mould. The principal feeding value of hay is in the albuminoids and carbohydrates which it contains, and healthy growing plants are much richer in these substances than ripe plants of the same species. It has been proved also by chemical analyses and feeding experiments, that the grasses and clovers contain the largest quantities of available nutriment when they are in blossom. Properly cured bay is almost as digestible and valuable in every respect as grass; but the common shrinkage in the weights of well protected cattle and horses during the winter seasons, is sufficient proof, that hay is generally much inferior to living grasses. Plants have the power to exclude air and unnecessary moisture from their internal parts; but when they are cut down and dried or only partially dried, they absorb water readily. Grasses can not grow without water, air, heat and sunlight; but when they die, these are the agents which cause them to decay rapidly. On September 27th, a frost killed the leaves of several species of trees on the college campus, but it did not injure the leaves of others. Within a day or two after the frost, the color of ripe leaves changed from green to yellow; while the color of unripe tender leaves changed to a dull black within an hour after they were exposed to the sun. I gathered some of the yellow leaves when they began to fall from the trees and placed them on panes of glass and sprinkled them with water several times during the following afternoon. The next morning, I found a yellow substance like wet yellow ochre on the panes of glass under many of the leaves. After wetting and drying them several times I found also, that all of the soluble matter which they contained had been washed out, and that nothing was left, except worthless woody fiber. By exposing blades of orchard grass and millet and the firmer leaves of maple and cottonwood trees to the weather when it was showery, I found that the soluble parts of the grasses were washed out much more rapidly than the soluble parts of the leaves of the cottonwood and maple. It is well known, that green plants can be dried and kept in a dark room without any apparent change of color or substance for years, and that they fade and change rapidly in other respects when they are fully exposed to the sun. Such facts indicate that the common methods of making hay should be abandoned. Then, how can we make and store hay for future use without our sustaining considerable losses of albuminoids and other nutritive matter? I will answer the question by giving the results of experiments which I have tried at different times. The over-drying or sunburning of hay in clear hot weather, was my first mistake. I found that such hay did not heat or sweat in the stacks like good hay; that it lacked the odor of good hay, and that it did not supply the wants of my cattle and horses in a satisfactory manner. Generally, when I have cocked partially dried clover hay in ordinary haying seasons, to prevent its being injured by the sun and dews, I was compelled to spread it out again to dry and the result was usually that I had bleached or blackened hay of inferior quality. I have never known heavy rains to fall on cured or partially cured clover hay, that did not reduce its value less than one half, even when well cocked

Experiments with corn

Sixteen acres of corn were grown on the grounds of the Iowa Experiment Station in 1889. The principal part of it was produced from the best ears of our last year’s crop of Learning corn, and the remainder consisted of Arleus and early Mastodon corn. It was grown on a black heavy soil, which was too wet formerly in wet seasons, to produce paying crops of anything, except grass; but last year it was tile-drained thoroughly. The greater part of the field had been used for many years as a pasture and the remainder, (perhaps five acres) was a part of an old field which had been used for different kinds of crops. It was well plowed early in September, 1888. Last spring, we ran over it twice with a disc harrow and once with a reversible harrow and then plowed it about eight inches deep. Then we ran over it again with a disc harrow and a reversible harrow and also with a heavy farm roller. It was planted May 2d and 3d, with a two horse planter in rows three feet and eight inches apart. From two to three grains were planted in each of the hills, which were thirty inches apart in the rows; but the entire field was thinned afterwards to two stalks in each hill. The field was harrowed twice with a Thomas smoothing harrow after the com came up; when it was divided into four lots, each of which was cultivated four times afterwards and hoed once. The south lot was cultivated each time with the Tower cultivator. The lot next to it was cultivated each time with the Eagle- Claw cultivator. The next or third lot, was cultivated with the riding Pearl cultivator, and the remainder of the field each time with the Albion Spring Tooth cultivator. The work of the Tower cultivator was excellent where oat stubble had been plowed under; but where old weeds or corn stalks were near the surface of the ground, it did not work well. The work of the Eagle-Claw cultivator was better than could be done by the walking or riding plows which are used in every neighborhood; because it pulverizes the surface of the ground better and leaves it level. But the Albion 248 Spring Tooth cultivator excels all other kinds which we have used, on all kinds of ground and in every respect. When our crop of corn was husked and measured during the latter part of October, the yield of the entire field proved to be eighty bushels per acre of sound shelled corn. I find from the reports of the Secretary of the Iowa Board -of Agriculture, that the average yield of corn in Iowa for the years 1883-8 inclusive, was 31 and 312/3 bushels per acre. The highest average yield per acre for a single year, was considered remarkable, being 411/4 bushels. When we compare such crops with our crop, we can not help asking, why are there such differences