Geographical and Geological SurveysWelch, Bigelow, 1875 - 96 strani |
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Zadetki 1–5 od 19
Stran 4
... object the preparation of topographical maps of the regions surveyed . Such maps have as their essential features absolute accuracy and minuteness of detail ; and in this respect they contrast strongly with the work of preliminary ...
... object the preparation of topographical maps of the regions surveyed . Such maps have as their essential features absolute accuracy and minuteness of detail ; and in this respect they contrast strongly with the work of preliminary ...
Stran 7
... objects may find room on which to be represented , a large scale must be adopted . It will also be not difficult to perceive that , in order to be able to prepare a map on a large scale , the preliminary topographical work must have ...
... objects may find room on which to be represented , a large scale must be adopted . It will also be not difficult to perceive that , in order to be able to prepare a map on a large scale , the preliminary topographical work must have ...
Stran 10
... object in view of building a railroad or cutting a ditch , wants a section of the line he has to pass over , or , indeed , sections of many lines , that he may choose the one best adapted to his purpose ; and he wishes to know the ...
... object in view of building a railroad or cutting a ditch , wants a section of the line he has to pass over , or , indeed , sections of many lines , that he may choose the one best adapted to his purpose ; and he wishes to know the ...
Stran 13
... primary triangles should be made as long as possible ; that is , the two ends must be as far apart as vision aided by powerful telescopes can be extended . The object sighted at one end of the line is a beam of the sun thrown by 13.
... primary triangles should be made as long as possible ; that is , the two ends must be as far apart as vision aided by powerful telescopes can be extended . The object sighted at one end of the line is a beam of the sun thrown by 13.
Stran 14
... object the fixing of the position of more points ; and this is carried on until the whole surface of the country has been cut up into triangles of suitable dimensions . In the British Ord- nance Survey over districts where the scale of ...
... object the fixing of the position of more points ; and this is carried on until the whole surface of the country has been cut up into triangles of suitable dimensions . In the British Ord- nance Survey over districts where the scale of ...
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accuracy already amount astronomical Atlantic Basin California chiefly Clarence King coal Coast Survey Colorado commenced Congress connected considerable continent contour lines corps determined distance earth École des Mines Engineer Bureau England eral Europe expedition expenditure exploration extended feet Fortieth Parallel Survey Fremont furnish geological map geological structure geological survey geologist given gold hill-shading idea important inch indicated interior investigation knowledge known Lake Lake Superior Land Office Surveys longitude Massachusetts material matter meridian metalliferous mineral lands mining school nearly obtained Ordnance Survey Pacific Pacific Railroad Surveys Pennsylvania points portion position present primary triangulation Professor James Hall progress Prussia published purpose Railroad ranges reconnoissance regard region west Report River rocks Rocky Mountains scale scientific sections sheets Sierra Nevada square miles surface territory tion topographical map topographical survey triangulation United States Engineer vertical
Priljubljeni odlomki
Stran 69 - Mining claims upon veins or lodes of quartz or other rock in place bearing gold, silver, cinnabar, lead, tin, copper, or other valuable deposits, heretofore located, shall be governed as to length along the vein or lode by the customs, regulations, and laws in force at the date of their location.
Stran 68 - An act granting the right of way to ditch and canal owners over the public lands, and for other purposes...
Stran 34 - For extending the triangulation of the coast survey so as to form a geodetic connection between the Atlantic and Pacific coasts of the United States...
Stran 68 - All valuable mineral deposits in lands belonging to the United States, both surveyed and unsurveyed, are hereby declared to be free and open to exploration and purchase, and the lands in which they are found to occupation and purchase, by citizens of the United States...
Stran 69 - States and those who have declared their intention to become citizens, subject to such regulations as may be prescribed by law, and subject also to the local customs or rules of miners in the several mining districts, so far as the same may not be in conflict with the laws of the United States.
Stran 16 - Baden, the new map was commenced in 1874, on a scale of 1 : 25,000, and with contour.lines at 10 metres' distance. The work is mainly a revision and correction of older surveys, and is expected to occupy six years, at a cost of about 80,000 florins. In Saxony, the original survey was commenced in 1780 and completed in 1806 on a scale of 1 : 12,000, the area of the kingdom being 5,600 square miles. A topographical map was issued in the years 1837-1860, in 22 sheets and on a scale of 1 : 57,600. A...
Stran 93 - All the attempts at working them have, however, proved to be unprofitable ventures ; although a great deal of money has been spent in this way at various times since 1765. The same has been the case with the other metalliferous veins of New England ; almost without exception the mines which have been opened on them have been disastrous failures. Eaton, Shelburne, and Warren, in New Hampshire, may be cited as typical localities, where flattering surface indications have led to extensive mining operations,...
Stran 39 - ... and base line to check the surveys, but what are called guide meridians and correction lines or standard parallels have been instituted, which are all run as nearly as human skill can effect it upon true meridians and parallels of latitude.
Stran 16 - ... 25,000, and with contour lines at distances of 5, 12|, or 25 feet, according to the nature of the country. The publication of the plane-table sheets was commenced in 1868, and in 1873 120 had been issued. There has also been, since 1841, a general map in process of publication, on a scale of 1 : 100,000, which will be comprised in some 400 sheets, of which nearly all are issued. These are engraved on copper and have the topography, or hillshading, indicated according to Lehmann's system, as modified...
Stran 68 - An act to promote the development of the mining resources of the United States," approved May tenth, eighteen hundred and seventytwo.