Page:Popular Science Monthly Volume 41.djvu/151

From Wikisource
Jump to: navigation, search
This page needs to be proofread.



��is a chance whether the insanity or drunken- ness, say, of the parent, will appear as such in the child or be transmuted in transmission to one or other of the alternate degenerate conditions. The present system of treatment has proved a disastrous failure ; short pe- riods of punishment can have no effect, either curative or deterrent. Everything points in the direction of prolonged or in- definite confinement in industrial peniten- tiaries.

Oscillations in Latitude. At the recent anniversary meeting of the Royal Society, the president, Sir William Thomson, spoke of the investigation of oscillations of latitude which has been instituted under the auspices of the International Geodetic Union. Comparative observations have been begun at Berlin, and at Honolulu, which is very near the opposite meridian to Berlin. The first several hun- dred determinations of latitude made at Honolulu during three months of a proposed year of observations, compared with the corresponding results at Berlin, showed that the latitude during that time had increased in Berlin and decreased at Honolulu by about one third of a second. " Thus we have decisive demonstration that motion, relatively to the earth, of the earth's in- stantaneous axis of rotation, is the cause of variations of latitude which have been ob- served at Berlin, Greenwich, and other ob- servatories, and which can not be wholly at- tributed to errors of observation." This, Prof. Foerster remarks, gives observationalproof of a conclusion which the author had expressed in 1876, to the effect that irregular move- ments of the earth's axis to the extent of half a second may be produced by the temporary changes of sea-level due to meteorological causes. It is proposed that four permanent stations for regular and continued observa- tion of latitude at places of approximately equal latitude and on meridians approxi- mately 90 apart, be established under the auspices of the International Geodetic Union. The reason for this arrangement is, that a change in the instantaneous axis of rotation in the direction perpendicular to the merid- ain of any one place would not alter its latitude, but would alter the latitude of a place 90 from it hx longitude by an amount equal to the angular change of the position

��of the axis. Thus two stations in meridians differing by 90 would theoretically suffice, by observations of latitude, to determine the changes in the position of the instantaneous axis ; but differential results, such as those already obtained between Berlin and Hono- lulu, differing by approximately 180 in lon- gitude, are necessary for eliminating errors of observation sufficiently to give satisfactory and useful results.

Swedish Wood and Iron. According to our minister in Stockholm, the two great products of Sweden after agriculture are wood and iron. The Norland is still covered for the most part with an extensive black forest, consisting largely of pine and spruce. Upon the great water-shed called the fjdd or Kblen (the keel of the country likened to a boat turned bottom upward) stand the chief timber forests ; and extensive lumber- ing operations are carried on along the nu- merous rivers and their tributaries that flow thence. At the mouths of most of the rivers are towns which take their names as well as their business and prosperity from the streams where are large saw-mills. Lumber operations are also conducted south of Stock- holm on both coasts, and there is a consid- erable export from Gothenburg; but the great bulk of the timber is cut and sawn in Norland, and eighty-five per cent of the lum- ber exports come from the north of Stock- holm. The Swedish lumber trade has as- sumed its present importance only within the present century, and in fact during the past thirty years. More than one quarter of the wooded area of Sweden, or 14,300,000 acres, belongs to the crown. The forests are supervised with great care, and all Sweden is divided into forest districts, and these, in turn, into revirs. Each district is under the supervision of a chief forest inspector, and each revir is guarded by a forest ranger and a number of under-keepers. Our minister thinks that the vast forests of Sweden will be preserved and maintained substantially as they stand to-day, and that Sweden's lum- ber export her greatest source of reve- nue will be maintained and kept good for ages to come. The Swedish iron, celebrated throughout the world, is soft and ductile, and preserves great pliability and strength. It still furnishes the raw material for the

�� �