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Show ,1 INVALUABLE NEW MAP GF NORTH AMERICA The most notable map publication of the year is the large geologic map of North America just issued by the United Unit-ed States Geological Survey. It re-presentsan re-presentsan exceptional type of entrrav-m entrrav-m and lithographic color work and is printfd in four sheets which fitted together to-gether and mounted make a map 6 feet 5 inches hisjh by 5 feet wide, the largest piece of work ever issued by the Survey Tne scale is 1 to 5,000,000, or 80 miles t tie hch, ai 1 the plan of projection i; in harmony with the universal world map on a scale of 1 to 1,000,000, in that it shows the units of publication of the world map, each of which embraces four degJees of latitude and six degrees of longitude. The color tcheme of the map Is a Btriking one. In all there are 42 color j dstinctions, varying from a brilliant re I to pale tints approaching white. These were produced by 14 separate p intins from lithograpnic stones, requiring re-quiring in manv places two or three ombinations of color to produce the disired effects. If the weight of paper an I heavy scones lifte 1 back and forth in the printing of this job were to be computed it would run into the hundreds of tons. The accurarcy of the" 'register," or fitting togetner of the color blocks in small areas throughout the map, is remarkable T e work was done in the Survey's own engraving and print-in? print-in? pi int, and it is believe 1 that cure are few if any otlv r escaolishmenis in t.'e United States capable of turning out such a production. The 42 color distinctions represent as manv devisions of rock strata. Thus the rocks of seven divisions of Paleozoic era are each represented re-presented by a color, besides three teparate colorsfor undifferentiated rocks and there are other colors for the divisions divis-ions of the Mesozoic, the Tertiary, and the Quaternary. The coloring of the map is both effective and pleasing. The scheme is systematic order from yellow in the upper partion of the geo'ogic column through greens, blues, ai d purples to pinks and browns at the base. The colors for the igneous roeke, both plu-tonic plu-tonic and volcanic, are mostly bright red. Viewed as a wall map, the map of North America shows only the larger geologic units, as the smaller divisions are represented by different shades and tints of the same or closely allied color which are indistinguishable at a moderate mod-erate distance. Viewed close at hand tr ese minor distinctions dis-tinctions can be read and the map can be used for detailed study limited only by the fcaL When it is used as a wall map the regions illustrating different types of geology stand out boldly. The great Canadian shield of pre-Cambrian rocks is represented by a subdued color i i a pattern simulating crystalline tex-t tex-t ire. Parallel bands of darker colors f ram New Brunswick to Alabama mark tne trend of the Appalachians, while t le broad area of blue and gray colors to the west represent the coal fields of the interior, and a fringe of yellow eolers to the east and south represents the Coastal Plain sediments. A brilliant vermilion coloring over mucn of the western part of the continent from Alaska to Central America strikingly portrays the volcanic activity in this i gion during the Tertian period, and the broad area of green and yellow in the Middle Wesl marks the last stages f iieposicion of sediments in the interior in-terior sea which covered thai part of North America in Cretaceous time and in the continental depressions in Tertiary Ter-tiary time, including manv of the great coal deposits of tne puohc domain. The map embodies all the available published daca and unpublished manuscript manu-script maps in the otfiivs of the Surve, and corrections from geologists in all parts of the country, based on a for n.-r geological map of Nurcn America, puo-lisned puo-lisned oy tne Survey in l'.tOo, in coop ri tion with tne Canadian and Mexican jg olojieal surveys, for the Interntion.il Geologic Congress which asse.noL-d in the city of Mexico in that vear. As an example of tne ioterest. taken in tni publication of the presenc m ip, it may be stated trial l.npoi taiit corrections 1 1 tne map of ldOti were receivej oy tne iiurvey from a leading geologise of Prance. Not only will the geologic map of Norcn America be indispensable as a wall map in colleges anj scnoois wnere g ology is taugnc, but .acn student ; will desire a copy lor tne study of broader problems in areal and renion.d geology and will wisn to carry a fuljed Copy on railroad trips across t ie continent. con-tinent. Tnis map is now on sale by tne Unite J States Geological Survey at the nominal j price ot 75 cents eacn. lc is safe u assume tnat any private map publishing nouse wouU caarge $5 to id a copy lor sued a map. i i ! Mrs. A. R. Tabor, Cnder, Mo., ' had oeen troubled with sick headache for aoout five .years, wnen sne began taking Cnamberiain's Tablets. sne has taken Cwo bottles of tnem and tney have cu: ed her. Sic neadacne is caused by a disordered sloinacntor wnicn these ' tablets are especially intendedfry tnein get well anj stay Well, ooid oy all dealers. |