Popular Science Monthly/Volume 11/August 1877/Popular Miscellany
Scientific Associations for 1877.—The French Association for the Advancement of Science will this year hold its sessions in August, at the city of Havre, under the presidency of Dr. Broca, the eminent archæologist. The Geological Society of Normandy will give an exhibition of the geological and paleontological products of that ancient province.
The annual meeting of the British Association will be held at Plymouth, on August 15th; Prof. Allen Thomson, President. The officers of the Association hope to be supported by the personal assistance and written contributions of philosophers of other countries, and they undertake to make preparation for the reception of the distant friends and associates who may give notice of their intention to be present at the meeting.
The officers of the American Association for the next meeting, which is to be held at Nashville, Tennessee, commencing on Wednesday, August 29th, are Prof. Simon Newcomb, President; Prof. Edward C. Pickering, Vice-President of the Physical Section; Prof. O. C. Marsh, Vice-President Section of Geology and Natural History; Prof. N. T. Lupton, chairman of the Chemical Subsection; Prof Daniel Wilson, chairman of the Subsection of Anthropology; R. H. Ward, chairman of the Subsection of Microscopy; A. R. Grote, General Secretary; F. W. Putnam, Permanent Secretary; William S. Vaux, Treasurer.
Shad in the Ohio River.—Mr. Spencer F. Baird, of the United States Fish Commission, in a letter to the editor of Forest and Stream, states that he has received a few specimens of a genuine white shad, four pounds in weight, taken from the Ohio River at Louisville, Kentucky—a direct result from the efforts made by the commission to stock the western rivers with shad. The letter gives a brief account of the work done by the commission toward introducing the shad into the waters of the Western States, beginning with 1872, when Seth Green planted 30,000 young shad in the Alleghany at Salamanca, New York, and 25,000 in the Mississippi near St. Paul. Later in the same year, the Rev. Mr. Clift placed 200,000 in the Alleghany at Salamanca, and a small number in the Cuyahoga and in the White River at Indianapolis. The same gentleman carried 2,000 young shad as far west as the Platte, at Denver. In 1863 about 160,000 shad were placed in the Greenbriar and New Rivers in West Virginia, and about 55,000 in the Monongahela in Pennsylvania and the Wabash in Indiana. Mr. Baird has been informed that for some considerable time forty to fifty shad have been taken daily at Louisville by a drag seine said not to exceed thirty or forty yards long, and that in the shoaler water of only three or four feet, while the regular steamboat-channel is ten or twelve yards deep and 250 yards wide.
A Remarkable Salt-Bed at Goderich, Ontario.—Dr. T. Sterry Hunt gave, at the late meeting of the Institute of Mining Engineers, an account of the layers of rock-salt in the geological strata of Goderich, Ontario, as developed by a boring recently made. The paper has been published in the Engineering and Mining Journal, from which we quote some particulars regarding two of the most important rock-salt beds reached in the course of the boring. A bed of rock-salt of exceptional purity was found at the depth of 1,060 feet, and another bed, not so pure, at the depth of 1,092 feet. Of these, the former is 25 feet thick and the latter 34 feet; they are separated from each other by a layer of less than seven feet of rock, and for practical purposes may be regarded as one. The amount of foreign matter contained in the twenty-five-foot bed is singularly small, being less than a quarter of one per cent. Its remarkable purity is seen on comparing this with the best commercial salts. Thus, Cheshire rock-salt contains of foreign matter 2.67 per cent., and the famous rock-salt of Cardona, Spain, 1.45 per cent, of impurities.
The salts got by evaporation from sea-water and from brines, with which our markets are in great part supplied, contain nearly as much impurity. "From data gathered by me," says Dr. Hunt, "and published some years since in a 'Report of the Geological Survey of Canada,' it appears that the amount of foreign matters in Turk's Island salt is 2.34; in Saginaw salt, 2.00; in Syracuse solar salt, 1.15; and in the boiled salt from the same locality about 1.50 per cent. Of the salt made at Goderich from the brines pumped from the salt-bearing strata of the region, three samples, analyzed by me in 1871, gave: for coarsely crystalline salt) 1.097; flaky medium salt, 1.282; and fine salt, 1.625 per cent, of foreign impurities. The fine salt, which is the least pure, is made by boiling, the others by slower evaporation. The analysis by Dr. Goessmann of another sample of Goderich boiled salt gave 1.50; while the rock-salt from the layer of 104 feet in Division VIII. of the section [the twenty-five-foot layer mentioned above] contains only 0.234 per cent., or less than one-sixth of the amount of foreign matter found in the boiled salt made from the Goderich brines."
About the English Sparrow.—A spirited but entirely courteous controversy is being carried on in the columns of our contemporary. Forest and Stream, about the English sparrow. The principal questions in dispute are whether this bird is useful as a destroyer of noxious insects, worms, and the like, and whether it banishes from its haunts all other species of small birds. The evidence is conflicting. Some of the writers say of the sparrows that they are "exceedingly quarrelsome among themselves," and intolerant of birds of a different species. When a stranger-bird makes his appearance among them, the fury of the whole sparrow community is turned upon him; they chase him hither and thither, giving him no rest until he is banished from the neighborhood. "They" (the sparrows) "let the orchards go to ruin," we are told, "for they will not eat every kind of insect." One writer sums up the case against the sparrows thus: 1. They have no personal attractions except their tameness; 2. They are practically useless; they may have been useful on their first arrival from Europe, but they are too much pampered to be so now; 3. They destroy fruit-blossoms; 4. They are often quarrelsome, and sometimes drive away useful birds. On the other hand, we are told that the sparrows destroy immense numbers of larvæ, especially during the winter; that they are not hostile to other birds; that they do not destroy fruit-germs. A writer who lives in Tenafly, New Jersey, says: "We have a few sparrows in the yard, and find their presence makes very little difference with the other birds. We have sixteen varieties of birds in the yard at this writing, viz., brown thrush, robins, catbirds, orioles, wood-robin, bluebirds, phoebe-bird, cuckoo, kingbird, and the rest warblers of different kinds. We find the most quarrelsome to be the kingbird and black oriole. These last are chasing almost everything that crosses their path."
Hygiene of the Eyes.—A series of questions touching the care of the eyes were recently submitted to Dr. E. G. Loring, Jr., by the Medico-Legal Society of New York. Dr. Loring replied in a paper which has since been published in the Medical Record. To the first question—namely, whether bad air has any direct effect on the sight?—the author replies that vitiated air has a specially irritating influence on the mucous membrane of the eye; and that bad air, as a primal cause, may set in train morbid processes which not only will affect the working capacity and integrity of the organ, but may even lead to its total destruction. The second question was, whether size and quality of type may cause disease of the eye? According to Dr. Loring, the smallest print which a normal eye can readily recognize at a distance of one foot is about 50 inch, and at eighteen inches' distance about 32 inch. The normal eye should never be subjected for any length of time to a type smaller than twice this size, or 16 inch, and it would be better, after middle-life, to employ a type even a little larger than this; but the employment of spectacles removes in a great degree the necessity of a larger type with advancing years. The finer the type, the closer the book has to be held to the eye, and the greater the demand on the focalizing power and the muscles that bring both eyes to bear at once upon the print. On the other hand, too coarse type is wearisome to the eye, requiring more exertion of the muscles that govern the movements of the eye. The distance between the lines should be about one-eighth inch; nearer than this is apt to be confusing, farther apart is also confusing. Heavy-faced type is preferable to lightface. An almost imperceptible yellow tint in the paper, "natural tint," is very desirable; pure white paper, especially if it has a metallic lustre with bluish tinge, should not be employed. The paper should be thick enough not to be transparent, should have a close, fine texture, and be free from sponginess. To the third question—whether too long and constrained attention to one object, without rest or variety, will cause eye disease?—Dr. Loring replies affirmatively, and assigns the physiological reasons. Finally, he was asked whether the angle at which light strikes the eye is important? He replies that the light should not come directly in front; neither should it come from directly behind. It should not come from the right side, because, in writing, the shadow of the hand falls across the page; and a moving shadow over a lighted surface not only reduces the quantity of light and leads to a stooping position, but it is also more annoying to the eye than a uniform reduction in the illumination of even a greater degree. The best direction for the light to come is from the left-hand side, and from rather above than below the level of the hand.
High Temperatures and Bowel-Complaints.—Dr. N. S. Davis, in a "Report on Clinical and Meteorological Records" communicated to the American Medical Association, an abstract of which we find in the Medical Record, reaches the conclusion that the bowel affections, so characteristic of this temperate climate, begin invariably with the first week of continuous high temperature, and that every subsequent occurrence of several days and nights of continuous high temperature causes new attacks to be increased in number throughout the month of July, less in August, and still less in September; that it is not simply the extreme of heat, but its duration, which determines the number of attacks; that this continuous high heat, to be efficient in producing these affections, must follow a protracted season of cold; and that, if we compare these deductions directly with statistics of mortality, we shall find them to conform in every particular in that the high rate of mortality follows exactly the same line. That fact was regarded as one of great importance in connection with sanitary measures which were to be adopted for the protection of life in infants; preventive measures must strike with the first week of consecutive high temperature. These conclusions were corroborated by quotations from mortality-tables.
Manurial Value of Spent Tan and Sawdust.—From careful analyses of spent tans and dyewoods and other similar waste materials. Prof. F. H. Storer, of the Bussy Institution, reaches the general conclusion that they contain but a very small proportion of fertilizing substances, and that practically, whether they be fresh or rotten, they have very little value as manure. Of fresh sawdust, even that from hard woods, he says that it can hardly be considered an economical manure; it is far inferior, for compost, to peat. But, curiously enough, the chemical evidence goes to show that it is for feeding animals rather than for feeding plants that sawdust might be put to use. Fresh sawdust, even that of pine trees, can be used with advantage as fodder in times of dearth. Twigs and leaves, as the clippings of vines and hedges, or bushes mown in pastures, are undoubtedly valuable both as manure and forage. Autumn leaves and the rakings of woodland, which consist for the most part of leaves that have not only fallen, but have been bleached by rains, may be classed as somewhat inferior to straw.
Wearing Qualities of Aluminium.—The comparative resistance of aluminium to change of color and wear, when brought into daily use, has been made the subject of observation by Dr. C. Winkler, of Freiberg, who finds, according to the Polytechnic Review, that it is inferior to silver in retaining color and lustre, being about on a par with German-silver in these respects; while it wears away more rapidly than silver, but less so than German-silver. Spoons made of all three materials, each having exactly the same weight, were used a year under precisely similar conditions, being placed in the same soups, sauces, sour salads, etc., and exposed alike to hot, acid, and alkaline solutions, and subjected to similar methods of cleaning. The aluminium turned to a dead bluish-gray color, and lost its lustre; the German-silver changed to a grayish—yellow; the silver lost only in color, retaining its lustre. Weighed at the end of the year, the silver spoon had lost 0.403 per cent., the aluminium spoon 0.630 per cent., and the German-silver spoon 1.006 per cent. For small coins. Dr. Winkler thinks that aluminium is to be preferred to either nickel or silver alloys.
Is Insanity on the Increase?—Do the conditions of human life, as they exist in modern civilized countries, tend to an increase of insanity? A glance at the statistics of the insane for any given country would seem to require an affirmative answer to this question. For instance, the ratio of insane persons in England in the year 1859 was 18.67 to 100,000 persons; in 1865 it was 21. 73; in 1870, 24.31; in 1876, 26.78. In other words, there is now one insane person to 375 of the population, while in 1859 the proportion was about one in 540. But, as is shown by Dr. Henry Maudsley, in the Journal of Mental Science, the increase is apparent only: more insane persons are registered now than formerly. Again, the establishment of numerous asylums, and the better care bestowed on patients, have had the effect of prolonging the lives of the insane; this, too, will in part account for the higher proportion of insane shown by the statistics. The question is incidentally raised by Dr. Maudsley, whether we cure more insane persons nowadays, when we treat them well, than our uninstructed forefathers cured when they treated them ill. "There is," he replies, "no evidence that we do." Here the statistics would seem to show that, under the old system, there was a higher percentage of recoveries. "Yet, it would be wrong," remarks the author, "to attribute the lower percentage of recoveries to the ill-success of our present mode of dealing with insanity; it is, no doubt, owing in great part, if not entirely, to the greater proportion of chronic and incurable cases among those who have been admitted during the last twenty-five years. Formerly, acute and violent cases only were sent to asylums, and they would yield a larger percentage of recoveries, as well, probably, as a larger percentage of deaths. Of the admissions fewer recover and fewer die each year now than then, the result being the steady accumulation of a residue of chronic and incurable insanity beyond what occurred then. It is a question," he adds, "deserving attention, whether the present practice of crowding the insane of all sorts into large asylums, where the interests of life are extinguished, and where anything like individual treatment is wellnigh impracticable, is so much superior to the old system in effecting recoveries as some persons imagine."
The Rocky-Mountain Locust in Manitoba.—The following notes on the appearance and migration of the locust in Manitoba and the Northwest in the summer of 1875 are taken from a notice, in the American Journal of Science, of a paper on that subject by George M. Dawson. In the year just mentioned the hatching of locusts began in Manitoba on May 7th, and on May 15th it was general. The movement began in July, and was most general during the latter half of that month and the early part of August. The direction was southeast or south. Other swarms of locusts came from the south across the forty-ninth parallel, with a wide front stretching from the ninety-eighth to the one-hundred-and-eighth meridian; these arrived before the Manitoba broods were mature. These were the extreme northern part of the army, going northward and northwestward from the States ravaged in the fall of 1874. Mr. Dawson thinks that the planting of belts of woodland would in time effect a general and permanent abatement of the grasshopper-plague, since they usually avoid such belts. Their journey southward was regardless of the direction from which their parents had come the preceding year; and those of Nebraska, Missouri, Kansas, and Texas, flew northward and northwestward, returning on the course of their parents, who had flown southeastward from that quarter. The normal direction of flight is toward the hatching-grounds of their parents, so that two years seem to be required to complete the migration cycle. The methods of prevention proposed are the cultivation and preservation of forest-trees; the protection of the prairie-grass till the appropriate time for destroying the young insects by fire; and the protection of insect-catching birds.
A New Wheat-Fungus in California.—Early in March of the present year the young wheat in certain districts of California began to exhibit on its expanded leaves yellowish-white patches of fungous growth. This peculiar species of "rust" or "mildew" appears to be new to California, and has been recognized by Mr. H. W. Harkness, of the San Francisco Microscopical Society, as the Erysiphe graminis of De Candolle. According to Mr. Harkness, the fungus appears on the expanded leaves in felt-like patches, from one-sixteenth to one-half inch in length, following the longest diameter of the leaf equally on both sides. It adheres with great tenacity, though, on examining sections of the leaf and fungus, no suckers are apparent. The leaf, at a short distance from the culm, soon turns brown and dries. In the earlier stages the mycelium is observed creeping over the surface, its filaments overlying one another until it forms a felted mass. To what extent the wheat will be damaged, it is as yet impossible to say. Adhering, as it does, closely to the plant, it doubtless appropriates the juices needed for maturing the grain, at the same time excluding air and sunlight from the tissues. Its visible effect is a weakening of the stalk, thus favoring decay.
A New Measure of Geological Time.—The amount of solid matter abraded from the land and carried to the sea as sediment, or in suspension, has often been estimated by geologists, and the importance of this suspended matter as an agent of geological changes has been fully recognized. But less attention has been bestowed upon the soluble matter washed out of the earth by every fall of rain and added to the waters of the ocean. This subject has been studied by Mr. T. Mellard Reade, whose results, as I set forth in his presidential address to the Liverpool Geological Society, we find summarized in the Nineteenth Century as follows: The author's first problem was to estimate the total quantity of solid material removed in the course of one year, by the solvent action of rain, from the entire surface of England and Wales, supposing the mean rainfall to be thirty-two inches. It is worthy of note that the variation of rainfall in different parts does not affect the quantity of dissolved matter to anything like the extent that might have been anticipated. True, the hilly districts of the west, in Cumberland, Wales, Cornwall, and Devon, intercept a large quantity of rain; but, then, these collecting-grounds are composed of old rocks, ranging from Cambrian to Carboniferous; and such rocks are, to a great extent, insoluble. On the other hand, in the southern and eastern counties the rainfall is much less than in the west; but, then, the rocks belong generally to Secondary and Tertiary formations, and are tolerably soft and soluble. A kind of compensation is thus established, the total quantity of solid matter carried off in solution in a given time being much the same in one river as in another. Roughly speaking, it may be said that where the rainfall is greatest the solubility is least; where the rainfall is least the solubility is greatest. It is needless to follow the details of the calculation by which the author is finally led to the conclusion that about 8,370,630 tons of solids are annually removed in solution by the rivers of England and Wales. Distributing the denudation equally over the country, the total area being 58,300 square miles, we obtain a general lowering of the surface to the extent of .000077 of a foot in a single year; in other words, it would require 12,978 years to reduce the surface of England and Wales by one foot through the solvent action of rain alone. Fewer data exist for extending this interesting inquiry to the Continent of Europe, and fewer still when we pass to other parts of the world. But, making the best of available data, and proceeding on the principle that "Nature, on the whole, averages the results," Mr. Reade feels justified in assuming provisionally that about one hundred tons of rocky matter will be dissolved by rain from every English square mile of the solid surface of the earth in the course of a year. All this dissolved matter, however far it may be transported by rivers, ultimately runs down into the sea. If, then, as commonly supposed, the sea contains only what has been washed out of the land, the results previously attained may help us to form some crude idea of the length of time which has been needed to give the ocean its present composition. Not to be irksome, we may pass over an array of figures and a number of provisional assumptions, in order to reach conclusions of general interest. These conclusions are, that it would take, in round numbers, 20,000,000 years to accumulate the quantity of sulphates of lime and magnesia contained in the vast bulk of the ocean, but only 480,000 years to renew the carbonates of lime and magnesia; with reference, however, to the latter constituents, it must be borne in mind that a vast quantity of carbonate of lime is constantly being removed from seawater for the supply of the hard parts of shell-fish, crustaceans, corals, and other marine animals, and consequently the amount calculated as present in the ocean is far from indicating the total quantity which is poured into it. But what are we to say of the chlorides, especially the chloride of sodium, which is the prime constituent of sea-water? The ocean contains so much of this salt, and the rivers usually so little, that we are driven to conclude from the author's calculations that it would take 200,000,000 years to renew the chlorides in the ocean!
Geological Changes in Colorado.—It is noted as an interesting fact by Dr. A. C. Peale, in the American Journal of Science, that Colorado, which now possesses the highest mass of mountains in the United States, and whose mean elevation is higher than that of any other State or Territory, was also one of the highest areas of the North American Continent in Palæozoic time. In very early time in Colorado there was archæan land rising above the Palæozoic sea. As the Carboniferous age progressed, this land diminished by encroachment of the sea, due to subsidence of the land. This subsidence continued through Triassic, Jurassic, and Cretaceous time, into the early Tertiary. At the close of the Lignitic there was a physical break, followed by a subsidence (at least locally) and subsequently by elevation, after the deposition of the Miocene strata. The elevation of the Rocky Mountains, as we now see them in Colorado, is the result of an elevation commencing in early Tertiary time and continuing through the period, accelerated perhaps at the close of the Lignitic, and the deposition of at least Lower Miocene strata. This elevation is probably still going on.
The Building System of Philadelphia.—A paper on "A Building System for Great Cities," published in the Penn Monthly, contains an account of what may be called the Philadelphia system, of separate houses for families of very moderate means—artisans, and even laborers. There are three primary forms of houses, viz., the two-story four-roomed house, the two-story six-roomed house, and the three-story eight-roomed house, the value of which is respectively $1,200 to $2,500, $2,500 to $3,800, and $3,000 to $5,000. They are always of brick, erected on stone-walled cellars not less than seven feet deep, fourteen by twenty-eight feet for the smallest houses, fourteen to sixteen by forty-two to forty-five feet for the six-roomed and the eight-roomed houses. All these are built in contiguous rows or blocks with a common wall between them. Since the inauguration of the system, which scarcely dates before the year 1862, building has made rapid progress. In 1867 it began to be specially active, and since that time an average of 4,500 houses yearly has been erected, of which 2,500 were two-story and 2,000 three-story. The writer of the paper in the Penn Monthly has learned, from a personal inspection of a district near the southern border of the city of Philadelphia, that three-fourths of the dwellings that have been erected two years or more are owned by those who live in them. In a space less than a mile square, and containing 4,000 dwellings, the proportion of vacant houses was less than two per cent. Certainly more than one-half of these dwellings were owned by their occupants, and often entire blocks of thirty or forty houses would show over ninety per cent, so owned.Are the Salts of Copper poisonous?—Dr. Bureq, M. Galippe, and others, having in communications addressed to the Paris Academy of Sciences asserted that copper is not poisonous after the manner of lead, and that it may be absorbed for a long time without injurious consequences, Dr. E. Decaisne has submitted to the same Academy the results of observations made by himself, from which it would appear that the reverse is the fact. We present a synopsis of Dr. Decaisne's paper, which we find in La Nature. He states that in 1864 he published a memoir entitled "A Medical Study on Absinthe-Drinkers," in which it was shown that a great many of the cheaper qualities of absinthe contain sulphate of copper, and that, of a hundred and fifty absinthe-drinkers observed by him, a certain number gave clear evidence of copper-poisoning. Fifteen samples of absinthe, purchased at wine-shops in Paris, all contained sulphate of copper in varying proportions: three of the samples contained it in the proportion of twenty-five centigrammes to the litre. Indeed, some of the distillers frankly admitted that they used sulphate of copper to color the absinthe. M. Decaisne cited a recent case of poisoning by acetate of copper, that of a young man of twenty-three, who showed all the symptoms of acute poisoning by copper salts, after having drunk some "eau de vie de marc," an inferior quality of brandy. Analysis of a sample of this brandy showed it to contain 1.164 gramme of acetate of copper to the litre. The liquor had been distilled in an apparatus that had lain unused for a year, and which had become filled with acetate of copper. French statistics show that sulphate and acetate of lead rank third among substances employed in criminal poisoning.