80 National Geograjphic Magazine. 



3. The topographic work of the Coast and Geodetic Survey- 

 will be utilized as far as it extends. 



4. The survey will be executed in a manner sufficiently elabo- 

 orate to construct a topographic map on a scale of 1 : 62,500. 



5. The topographic reliefs will be rej)resented by contour lines 

 with vertical intervals varying from ten to fifty feet, as such in- 

 tervals are adapted to local topography. 



6. As sheets are completed from time to time copies of the 

 same will be transmitted to the commission. 



7. When the work is completed and engraved for the Geologi- 

 cal Survey, the Commission, or other State authorities, may have, 

 at the expense of the State, transfers from the copper plates, thus 

 saying the State the cost of final engraving. 



8. The survey will be prosecuted at the expense of the Geologi- 

 cal Survey for the months of July, August and September, Dur- 

 ing the last half of the month of September the Commission shall 

 examine the work executed up to that time, and if the results, 

 methods and rates of expenditure are satisfactory to the Com- 

 mission, the expenses of the work for the month of October shall 

 be borne by the State of Massachusetts, for the month of Novem- 

 ber by the Geological Survey, and the work thereafter shall con- 

 tinue to be paid alternately by months, by the Geological Survey, 

 and the State of Massachusetts severally. But as the larger ex- 

 pense incident to the beginning of the work is imposed on the Geo- 

 logical Survey, at the close of the work the State of Massachusetts 

 shall pay such additional amount as may be necessary to equalize 

 the expenditures; provided that the total expenditure of the State 

 of Massachusetts shall not exceed forty thousand dollars (140,000) ; 

 and if the completion of the survey of the State of Massachusetts 

 and the preparation of the necessary maps on the plan adopted 

 by the survey shall exceed in amount eighty thousand dollars 

 ($80,000), then such excess shall be wholly paid by the Geologi- 

 cal Survey. 



The commissioners suggested some minor amendments to this 

 proposition, which were accepted, and under these provisions 

 work was commenced and carried forward continuously to its 

 completion. The field work of the state was finished with the 

 close of the season last fall, and the drawing of the maps is now 

 substantially done. The work was done in the field with such 

 accuracy and such degree of detail as to warrant the publication 

 of the map upon a scale of one inch to a mile, or, what is prac- 



