Arizona republican., 1899-01-21
SOLD AT
HARD WORK TO MAKE MAPS.
Years of Labor Are Sometimes Given
 to One Photographic Product.


 to One Photographic Product.
 
 Few people have any idea of the inn mense labor expended upon the pro duction of the best maps. Prof. Wag- ner, who occupies the chair of geog- raphy at the University of Gottingen, Germany, was talking about it the other day. This famous geographer has just completed the latest revision of his Atlas of School Geography.
 ''I revise the Atlas about every two years" said the professor. Tt requires several months of my time; and in ad- dition to this I have to be on the look out every day for news of fresh discov- cries, corrections of errors that have crspt into the maps, new political boundaries, new temperature Obs9rva- tionS in the Amazon basin, for instance, where few meteorological records have been kept, which may effect the posi- tion of the isOthermal lines on my maps, and great varie-y of other in formation which necesSitates many changes on my map plates of more or less importance. 1 have to keep on file all the maps from explorers which are published by the geographical so- cietieS of all lands. It is from these maps that most of our information about new discoveries and the correc- tion of errors is derived. Then there are the map sheets of detailed topO- graphic survey, issued by the govern ments of nearly all civilized lands. They now number thousands and they must be in the libraries of all first-class map publishing houses which aspire to keep their maps fully abreast of geo. graphic progress.
 There is also great deal of author itative literature giving many geo. graphical facts, such as the distribu- tion of agricultural products in a coun- try, which may be clearly indicated on the maps We make. All this informa- tion has to be classified and pigeon holed ready for use when the time comes for the next map revision
 Many persons might think that the most barren and scantily peopled parts of the world would not often require correction on the maps; but this is not so. In the Arctic regions, for instance, within short time Peary visits an un- known part of the northeast coast of Greenland and finds a channel leading far west and separating the mainland as far as is determined from the is lands further north; Nansen discovers new facts about the depth of the Are tic ocean, gthe movements of Arctic cur rents, mean temperatures, etc, and pushes his work within 250 miles of the north pole; then Jackson appears with an entirely new map of Franz Jo- sef Land which completely changes our ideas of the geography of that region; and Tyrrel1 traverses part Of North America west of Hudson's bay never before visited and finds new facts for the maps, and other Canadian explor- CTS trace to Hudson's bay the rivers that drain the country to the south of that inland sea. Every year on an av- craze about 200 hitherto unknown reefs and rocks and other dangers to navigation are discovered and must be noted on many maps.
 It is the business of the geographer to take all this immense volume of new information and use it with critical care. He can tell within narrow limits what degree of credence is to be given to the work of each explorer and he re- Jects a great deal of information which | does not appear to him to be based up- on sufficiently careful or competent re- search
 When the Frenchman Sissy made the | large map of Africa, to which he de- voted great deal of his time for eight | years, he used as his sources of infor- | nation nearly 1,S00 route maps and other maps of the continent l. took a | great deal of time to sift from this 1 enormous mass of material the facts | he selected to present on the largest 1 map Of Africa yet produced
 One of the handsomes- cartographic | works of recent years is the atlas of the German colonies which Paul Lang hans Of Gotha, Germany, has recently | completed after about three years Of | assiduous labor. He neglected no source of valuable information in car rying out this undertaking, and the | sixty n ap pages give the results of the | latest md best geographical researches | amo1g Germany's colonies all over the | word. As is the habit of the best Se1-Ilan map makers. he gives the sources Of all the information he has placed on his maps
 To prepare this map of the little Marshall island protectOrate, for in | stance, he used seYenty-six different | maps, including official charts. like the | Admiralty surveys and the map mater | lal prepared by the American board of | commissioners for foreign missions of | Boston.
 He consulted 120 route surveys and | other maps of the semi-arid posses | sions of the Germans in Southwest Af- | rica 10 make his eight-page map of that | region; and every wagon road, well. bit | of grazing area, mining prospect and | hamlet in the whole district is shown | with fine effect.-New York Sun.