Page:Science vol. 5.djvu/237

 I 13. ISS5.]

��The toQg-dlsputed questions as to the ancient bed of the Ama Darliv, or Oms. sppear to have received a final settlement lu the publication of the studies ot EoDShln of St. Petersburg. According to him, the Tirer has nerer direcUy emptied into the Caspian; but it is probable that at some period an indirect communication has existed between Ihem through Suri-Kamlch Lake and the Uzbol, irhich drained It. The lake was ot much greater area, and its overflow reached the Caspian by the Uiboi: lis character was saline or brackish. Were this stale of things restored, we should have an immense Turanian sea, composed of a northern basin corresponding to that of the Sea of Aral, and a southern one corresponding to the Sari-Kamich area, connected by a wide but shallow neck of water. Into the former the Sir-Dariu would empty, wllh the Sarl-Su and the Chin; into the lat- ter, the Onus, the Tedient, STid the Slurghib, The overflow of brackish water would find its way by the Uibol to the Caspian.

Those interested In the question of lakes with two ODtlets would do well to incite eiptoratlon of Frances Lake la the North-west territory. This lake, discov- ered many years ago by Robert Campbell, now of Winnipeg, was reached by him from the head waters of the Liard River, ascending, Recording; to his ac- count, a small stream actually proceeding from the Ikke. To his surprise, on the other side he found a commiinjcatlon, during the time of high water, with the head waters of the Felly River. In 18^15 infor- mation received from officers of the Hudson-Day company at Victoria, by those of the International telegraph expedition, was to the effect that the Pelly communication wa^ the chief one, and that a lower- ing of its bed hod turned the drainage permanently north-westward, and llie connection with the Llard had become nearly or entirely dry. This has since been indicated on moat charts; but, as the lake cov- ers some four bnndred and fifty square miles, fuller ■nd conflrmatory evidence would be very desirable.

K Liard is an allluent of the Mackctuic, and the > of the Yukon River. U

��HE STATE SURVEY OF NEW FORK.

��veto of the appropriation for this survey by

tile Ute governor of New York catised only a partial suspension of its functions. The survey eiists by reason of an organic law creating the coromission, nnd deSning its powers. Only by the repeal of this law can the survey be abolished. Its work has been confined to a triangulallon so accurately executed as to form a reliable basis for all local surreys and topo- graphical work; but the value of such careful meas- urements is somewhat difficult for the unsclentlflc man to understand, and the results are not immedi- ately apparent.

To remove all doubts r^arding the excellence and economy of the work under their control, the com- missioners requested an investigation by the U. S, coast and geodetic survey. After a full examination

��of the records of eight years' work. Superintendent Bllgard transmitted them to the state authorities, with his full indorsement.

By this appeal to a most competent authority, the commissioners and director of the New-York state survey have established the fact that the work slowly accomplished with small appropriations since 1876 has been done in the best way and at a small cost. Their report just made to the legislature, having vin- dicated the work of the past, recommends a radical change In the future policy of the survey. It is urged that New York ihould be warned by the ex- perience of Massachusetts that a triangulallon not immediately followed by a detailed topographical sur- vey gives but little satisfaction lo the people. '[ he citizens of a state want reliable maps which they can use, not mere skeleton maps which are only available for surveyors. The board therefore recommends that the l^islature enlarge its powers, and increase the appropriations for the stale survey, so that topo- graphical surveys may be at once begun in at least three counties, and be carried forward on such a scale as to |)ermit of the economical performance of the work. The cost of the topographical work Is esti- mated at from ten dollars to twenty dollars per square mile, depending upon the character of the country, and the scale of expenditure recommended is forty thousand dollars per annum. For this sum, com- plete maps of from three to five counties could be made each year, and the maps, by counties. Issued within a year after the Beld-work is done. It Is pro- posed to have the U. S. coast and geodetic survey complete the primary and secondary triangulations, leaving the funds of the state U> be used for tertiary tri angulation and topographical work.

The experience of the director ot the suney, who Is by law the engineering member of the state lioard of health, has proved conclusively tke wide-spread need of topographical maps to aid in the sanitary work ot the state. The commissioners therefore affirm that there is pressing necessity for topographi- cal maps for sanitary works on water-supplies and drainage; that no survey can meet the wants of 'lie people that does not result in a reliable map suf- ficiently detailed for ordinary practical and scientlflc purposes; and that the people have a right to expect that the benefits of the survey will be made tmnie- iliateiy available In the form of useful maps.

��The only known way of measuring the density of

the earth is through the 'gravitation constanC which expresses the attraction exerted by a known mass at a given distance. The bodies whose attractions have been measured are either mountains or portions of the earth, as in the well-known cxperlmeiils of Maske- lyne and Airy; or portable masees of lead, as used by Bailey and others. The difficulty in the way of Ihe former experiments is the necessary uncertainty of the density of those portions of the earth's mass In

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