GEOGRAPHY OF NORTH AMERICA. 229 



preliminary computations show that the errors of closure in 

 the triangles do not exceed those of the principal surveys of 

 Europe and this country. The secondary and tertiary tri- 

 angulation has also been extended over about 1700 square 

 miles of the same district, including the greater part of five 

 counties immediately west and northwest of Albany. With- 

 in this area almost every town, village, and hamlet, as well 

 as points a few miles apart along the important roads, has 

 been located. One hundred and seventy-five miles of coun- 

 ty boundary, including the whole or parts of nine counties, 

 have been marked with granite monuments four feet hisrh, 

 and the position of a large number of them has been fixed 

 trigonometrically. A map of this region will soon be con- 

 structed. The local surveyors have already begun to base 

 their surveys of private property on the state triangulation, 

 and deeds are already on record in which the position of the 

 land is described by giving the distance and direction of 

 the nearest survey monument the use of the needle being- 

 abandoned. 



Very little field-work has been undertaken the past season 

 in the second state survey of Kentucky, under Professor N. 

 S. Shaler, but progress has been made in the publications. 

 The first four volumes of the economical reports are com- 

 pleted, the fifth and sixth each about half done, and matter 

 enough has accumulated for the completion of the unfinish- 

 ed volumes. These volumes contain over fifty memoirs on 

 the various resources of the commonwealth. A first vol- 

 ume of scientific memoirs has been published and a second 

 commenced. Two volumes of photographic views are also 

 ready for the press. Chemical analyses of over six hundred 

 different samples of the products of the state have been 

 made. Biennial appropriations are made for the continu- 

 ance of this survey, which has now been in operation six 

 years. 



Pennsylvania has also its second geological survey, under 

 the direction of Professor J. P. Lesley, which practically 

 commenced work in June, 1874, with appropriations provid- 

 ing for its continuance until the close of next year. Pro- 

 fessor Lesley has kindly furnished so admirable a digest of 

 its operations that it is given in very nearly his own words. 

 A small part of it has reference to the earlier as well as the 



