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The resolution of the Assembly contemplates nothing more, as to the botany of the State, than a list of its productions and the preservation of specimens of each. After making the necessary researches to complete the list, classifying the specimens, and arranging them in their proper order in volumes prepared for the purpose, the work will be consummated. The whole number of specimens will require an ordinary bookcase about six feet
PLAN OF SURVEY.
When we take into consideration the extended area of the State, the variety of formations which it embraces, and the numerous requirements contained in the resolution, it must be manifest that the contemplated survey could not be executed by a single individual in less than fifteen or twenty years; if indeed, a single individual could be found equal to the task. The survey of the State of Massachusetts, by Professor Hitchcock, was completed in two years; but, as he states in his report, he was already familiar with tile geology of a large portion of the State, from his own observations or the published accounts of others, and his personal examinations did not extend to its zoology or botany. Massachusetts has an area equal to about one-sixth of that of New-York. Assuming that the survey of Massachusetts was executed in the shortest practicable period of time, a single individual, even with the advantage of some acquaintance with the mineralogical constitution of this State, would require twelve years to exainine its geology alone. As the principal object of the survey is to procure information, which may be applied to useful purposes, it is desirable to complete the work as soon as possible, in order that the results may be available at the earliest practicable day.
It is proposed, therefore, to divide the State into four districts as to the geological part of the examination, and to assign to each district two geologists and a skilful draughtsman. By associating two observers in each district, it is supposed that an advantage will be attained on the score of accuracy through the suggestions, which may be mutually made during their investigations, and that the gain in point of time and expense, by a greater subdivision of the State, if the examination of each district were to be conducted by a single individual, would be undeserving of consideration in comparison with the advantage referred to.
In a division of the State for a geological survey, it is manifestly not equal, so far as a distribution of labor is concerned, to adopt a rule, which shall regard merely the superficial contents of the different parts. Some districts will embrace a greater variety of formations than others, and present greater facilities for the prosecution of the contemplated investigations. But, on the other hand, it is not clear that the adoption of a different rule would obviate this inequality, as particular sections, which exhibit few apparent objects of interest, may, on a nearer view, be found wor. thy of a very critical examination. It has been thought proper, therefore, to divide the State as equally as possible, into districts of the same area, with the exception of the northern primitive district, which, on account of the unsettled condition of a large portion of it, will oppose greater obstacles than cultivated sections to a thorough examination of its mineralogical structure. Thus the county of Hamilton, with an area of seventeen hundred square miles, contains only 1,654 inhabitants. In making the division regard has been paid, as far as practicable, to continuity of character in the strata running through the several districts. Thus, the primitive formation along the Hudson river, from Washington and Saratoga counties, and including the Catskill mountains and the Highlands, to the southeastern extremity of the State, has been thrown into the first district; the northern primitive formation from Lake George to the St. Lawrence river, including Hamilton county, comprises the second district; the counties including the salt springs have been assigned to the third district; and most of the counties in which a continuation of the coal formation of Pennsylvania may be expected to be found, to the fourth district. From the great variety of formations, which enter into the geological constitution of the State, this rule of division is necessarily imperfect, nor is it, indeed, deemed very material; but it may be convenient in some cases, by enabling the observers to run out a particular range of rocks to its termination, without going beyond the limits of the districts assigned to them.
It has been customary in extensive surveys of this description, to divide the region to be explored according to parallels of latitude or longitude. This is, undoubtedly, the most scientific mode of proceeding; but as the proposed survey of this State contemplates mainly objects of utility, and as maps of the several counties have already been constructed, exhibiting the minutest municipal divisions of the State with the greatest accuracy, it is deemed
preferable to make the districts conform to statistical boundaries, which are well known, and to present the results of the survey in maps constructed on the same principle.
The proposed districts are as follows:
973 396 76 63 22 496 172 216 765 760 919 1,459 1,096
657 624 626 515 621 200 800 807
932 1,652 1,700 2,717
shown, exceeds the actual area of the State, which is 45,658 square miles.
The county maps contained in Burr's aulas, may be adopted as a basis for the geological purposes of the survey. They were constructed with the assistance of the late Surveyor-General of the State; and they are, with respect to the statistical divisions existing at the time they were prepared, exceedingly accurate. The scale on which they are constructed, gives 21 miles actual measurement to one inch on the map, or a proportion between the map and the area, which it represents, of 1 to 158,400. In the atlas, in which it is proposed to exhibit the detailed results of the survey of the State of Maryland, now in progress, the county maps will be on a scale, which will make the proportion of each map to the surface represented by it, as 1 to 50,000. Taking the scale of the county maps in Burr's atlas as a basis, the results of the proposed survey of this State would be exhibited in maps bearing to the contemplated maps of Maryland, a proportion of 1 to 3.16; that is, every actual measurement in this State, would be represented on a scale more than two-thirds less than
such measurement in Maryland.
There is unquestionably an advantage in exhibiting the results of the survey on the largest scale consistent with convenience; but it is believed that, for almost every practical purpose, the proportion proposed will be sufficient.
The geological formation of the entire State should be exhibited, on a greatly reduced scale, in a single map. The most convenient size will, perhaps, be a medium between Burr's map of the State, forming a part of his atlas, and his large map published by the Surveyor-General in 1829. The former is on a scale of about eighteen miles to the inch, or, in proportion to actual measurement of the territory represented, as 1 to 1,140,480, and the latter on a scale of seven miles to the inch, or as 1 to 443,520. The latter is about four feet six inches in length, and is inconveniently large for examination. A scale of twelve miles to the inch, or as 1 to 760,320, actual measurement, would give a map of convenient size for examination, and sufficiently so for the purpose of affording a correct view of the principal features of the geological constitution of the State.