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The following factors controlling the concentrations of thirteen metals (Zn, Cu, Pb, Bi, Cd, Ni, Co, Hg, Ag, Cr, Mo, W, V) in sea-water were studied:1. precipitation of insoluble compounds with ions normally present in aerated sea-water,2. precipitation of sulphides locally in reducing environments,<br...

Two fundamental methods for studying aquifer hydrology are now in use. The first, applied many years ago, consists of detailed observation of aquifer inflow, outflow, and storage changes, and their variations in time. By analysis of these observations, estimates of the perennial recharge to the aquifer and other pertinent hydrologic...

Pond Creek in west‐central Oklahoma drains an area of 319 sq mi above the gaging station near Fort Cobb, Caddo County. Ground water, contained in the Permian Rush Springs sandstone under water‐table conditions, moves toward the creek at an almost unchanging rate. The discharge of ground water into the creek...

Our problem is founded on the fact that on the one hand every man's reading time is limited, whilst on the other hand there must exist, somewhere among the millions of items of literature available, the particular ones which contain the ideas most apposite to his needs, if only there...

Uranium minerals and radioactivity anomalies occur in many silverlead veins and chalcedony veins and vein zones in the Boulder batholith of southwestern Montana. Pitchblende has been identified in a few silverlead veins. These silver-lead veins occupy shear zones along which there is no evidence of large-scale lateral displacement. The wall...

Among the rivers studied by us two broad types may be distinguished. Channels in the semi-arid areas scour at high discharges so that the bed lowers nearly as much as the water surface rises. Detailed data on the middle reaches of the Rio Grande in New Mexico during the spring...

Flow in many of the streams and springs in the area covered by this report increased as a result of the Arvin-Tehachapi earthquake. Although this increase in flow appears to have been temporary, there was still evidence of it in some of the streams and springs as late as...

There have been very few published records of the occurrence of the acanthocephalan parasite Macracanthorhynchus ingens (von Linstow, 1897) in North America. Chandler (1942) and Moore (1946) reported 11 o 13 raccoons (Procyon lotor) trapped in Angelina County, Texas, infected with these intestinal parasites. From 1 to 90 worms occurred...

The distribution of dynamic pressure behind a Harris' hawk's wing was sampled using a wake rake consisting of 15 pitot tubes and one static tube. The hawk was holding on to a perch, but at an air speed and gliding angle at which it was capable of gliding. The perch...

Alluviation along the North and Middle Loup rivers in Valley County, Nebraska, produced a series of alluvial silt beds on which are developed five interstadial soils of Brady (?), Cary and Mankato (?), Mankato (?), early Recent and late Recent age. No deposits of Illinoian age were found and in...

The principal spawning grounds of lake trout (Salvelinus namaycush namaycush) in United States waters of southern Lake Superior are on rocky shoals at depths of less than 20 fathoms. Most spawning occurs in October and early November. Of the mature fish collected on or near the spawning grounds, 60...

The use of internal standards in the analysis of ores and minerals of widely-varying matrix by means of fluorescent X-ray spectroscopy is frequently the most practical approach. Internal standards correct for absorption and enhancement effects except when an absorption edge falls between the comparison lines or a very strong emission...

Investigations on infectious diseases of Pacific salmon due to micro-organisms other than viruses are reviewed. The etiological agents include trematodes, fungi, protozoa and bacteria. Bacteria have been found to be the most important agents of disease in the several species of Pacific salmon. Kidney disease, due to a small, unnamed...

Viruses are probably the cause of a wide spectrum of fish diseases. Although relatively few virus diseases of fish are known today, some of the diseases of unknown etiology, as well as some diseases presently accepted as due to bacteria, protozoa, fungi or nutritional deficiencies, possibly will be recognized eventually...

The method of calculation described is useful for the types of work of which examples are given. It is also useful in making rapid comparison of the activities that might be expected from several different elements. For instance, suppose it is desired to know which of the three elements, cobalt,...

1. 1. A study was made of the ability of 28 different culture media to support growth of 5 strains of Trichomonas gallinae with their normally associated bacteria. A standard inoculum of 50 protozoa was used, and the cultures were incubated at 35 ?C. Based upon the number of positive...

Nearly all the water used on Long Island, N. Y., is derived by wells from the thick and extensive water-bearing formations that underlie and compose the entire island. The unconsolidated deposits, consisting of sand, gravel, and clay, range in thickness from a few feet in northern Queens County to more...

The alkaline stock at Mount Monadnock, Vermont, described briefly by Wolff (1929), has been restudied in detail. Its petrography and structure are discussed here and conclusions are drawn as to its mode of emplacement. The stock consists of plutonic and hypabyssal rocks which intrude folded Ordovician (?) schist and quartzite. The longer axis, trending north-northwest across the strike of the country...

Total‐intensity aeromagnetic surveys of the Aleutian Marshall, and Bermuda Islands were completed in 1948. The anomalies associated with the Aleutian volcanoes are attributed mainly to topographic relief and are not an indication of the degree of volcanic activity. Eniwetok presents a magnetic pattern that would be produced by an irregular‐shaped rimmed depression in the basement, modified by the two adjoining seamounts, and differs from...

The sedimentary iron-formations of Precambrian age in the Lake Superior region can be divided on the basis of the dominant original iron mineral into four principal facies: sulfide, carbonate, oxide, and silicate. As chemical sediments, these rocks reflect certain aspects of the chemistry of the depositional environments. The major control, at least for the sulfide,...

One of the very obvious geologic phenomena that is continuously in operation throughout the Earth's land surface is erosion, the process of wearing away the soil or the surface mantle. The falling of rain drops on an unprotected slope, the flow of water across land or in a channel, the borings of a rodent, the...

Production records for 1885, 1891–1908, and 1929–49, indicate cyclic fluctuations for several important species of fish. The average annual take (all species) of 3,582,000 pounds in 1929–49 was 3,503,000 pounds below the 1891–1908 mean of 7,085,000 pounds. Decline in the output of lake herring alone from 5,841,000 pounds in 1891–1908...

Investigations concerning the life history of the Yellow-throat were made in southern Michigan during the spring and summer of 1938. Supplementary information was also obtained at Arlington, Virginia, in 1940 and at the Patuxent Research Refuge, Maryland, in 1947.....Resident males established territories almost immediately upon arrival in spring. In southern...

The Upper Mississippi Valley zinc-lead district covers 2, 500 square miles of Wisconsin, Illinois, and Iowa. It is one of the oldest mining districts in the United States, as lead mining by settlers began in 1788. Zinc has been mined since 1859, and the present production is more than ten...

Drawing his inspiration from the theories on metamorphism by reaction in the solid state, and from some observations, Rene Perrin in his article 'Perrin, Rene, Le metamorphisms generateur de plissement, Annales des Hines, Paris, October 1935.' "Metamorphism, the generator of folding" stated in 1935: 1) that some "sudden arrest" of regional...