SCIENCE. 



AN ILLUSTRATED JOURNAL PUBLISHED WEEKLY. 



» Verite sans peur. 



NEW YORK: THE SCIENCE COMPANY. 



FRIDAY, JANUARY 1, 1886. 



COMMENT AND CRITICISM. 



To many people in this practical era, the mani- 

 fest usefulness of work done affords the only 

 available standard of judging every tiling. It is 

 worth the while to see how the coast survey abides 

 this test ; for it can point to its system of charts 

 covering every harbor of prominence in the coun- 

 try, and nearly all the shore-line between them, 

 all the principal rivers to the head of tidal influ- 

 ence, and Lake Champlaln ; to its researches and 

 publications relating to terrestrial magnetism, and 

 its magnetic charts ; to the tide-tables, published 

 annually, of the ports on the Atlantic, Gulf, and 

 Pacific coasts ; to the ' Coast pilots ' for the At- 

 lantic and Pacific coasts and Alaska ; to its ex- 

 plorations and discoveries in physical hydrography ; 

 to its transit-of -Venus and eclipse expeditions, and 

 longitude determinations in Alaska and in foreign 

 countries ; to its work on the Isthmus of Panama ; 

 to the numerous scientific publications on all sub- 

 jects relating to or connected with its work ; to 

 the determinations of the force of gravity in all 

 parts of the world ; to very considerable improve- 

 ments in geodetic and field-astronomical instru- 

 ments ; and to the present perfected system of 

 weights and measures, which has secured har- 

 mony not only within the United States by sup- 

 plying standard weights and measures to every 

 state, to the principal custom-houses, and to the 

 agricultural colleges in the several states, but also 

 between our own country and foreign nations. 



Such an amount of scientific and practical work 

 of the highest merit could not possibly have been 

 accomplished except under the wisest organization 

 and the most efficient supervision. The character 

 of this work is itself the sufficient argument for 

 the maintenance of that organization. With so 

 exceptional a record of work actually accom- 

 plished, embracing so much that is of immediate 



No. 152. — 1886. 



economic bearing upon the welfare of the coun- 

 try and the conservation of national interests, the 

 survey need have little fear of hostile criticism, 

 and, least of all, that having its origin in personal 

 or political motive. The obviously useful charac- 

 ter of a large part of this work shows that it is 

 of real and direct value to the nation, apart from 

 its purely scientific merit. 



There is no portion of North America where 

 complete and long-continued series of tidal obser- 

 vations are more important, and will yield more 

 interesting results, than the coast of Canada. The 

 great rise and fall in some portions, and the anom- 

 alous conditions and irregular and unequal tidal 

 cm-rents prevailing along its deeply indented shores, 

 render a careful study of them a matter of serious 

 interest from both a scientific and practical point 

 of view. We are glad to see that the matter has 

 been attracting attention among our neighbors, 

 and that the different commercial bodies of Can- 

 ada have moved in the matter. A report on the 

 subject by a committee of the British association, 

 at the Aberdeen meeting, shows what has been 

 done, and what is proposed. The matter is one 

 more of general than local importance. As such, 

 it appears to be well worthy the attention of the 

 imperial government, which, at small cost to itself, 

 can here properly come to the aid of the colonial 

 department of marine, in the interest of the com- 

 merce and navigation of the world. Tidal obser- 

 vations on the eastern coast of America have 

 gained a new importance since the coast and 

 geodetic survey has confirmed by recent observa- 

 tions its announcement, some years since, that 

 there are tidal fluxes in the Guff Stream, and 

 variations of its velocity due to half-monthly 

 changes in the relative sea-levels of the Atlantic 

 and Gulf of Mexico. 



Judged by the result, it would seem that the 

 civil engineers' convention, recently held at Cleve- 

 land, to consider the relations of civil and mili- 

 tary engineers, found, that, like an historical 

 gathering at Ephesus, it had come together with- 



