| Show UW S Wt W Knowledge of iw HoW sound May be Gained by 7 1 Observation TO VISIT WEATHER BUREAU S 01 Hull Cl lU 1 0 be by 11 Dr Wy W VI Wrector rector of Signal Station it nature study Iud yesterday t Prof Cummings tie I t of f v r It the child make the At t Will th law Jaw ln In stud taught according to the best M 1 ItAl Hi II cf f th modem school Thus Thull t I i a i MM learn from experiments experiment K II he may ma be told iome orne 9 HI i 31 t op n to 10 ordinary obena 1 tJI i sund und does He may mil be b sound woven of th the air the i j flU r when the powder mag maga iii on Arsenal Arenal hill hili exploded years brol e mOIl of the In the tha H of hi CJ how fOund Mund ol of olce Ke often orten precipitates the I humal i t of the avalanche In the Alps how fJ 1 J Ji rI of a Pl tol In a lighted room At may ma put out the lamp or ran can at tit The p f and other phe phel should hould follow not precede the tho 7 l rr te fads fact percept obtained 1 lem ein observation j LAWS LA WS OF O SOUND Tj a 1 of sound therefore Arc lIt it de by b the Ihl u ule e of the pen tHun showing the of Its II vibration Ibra ning to Ita 1111 length then Ihen It Is III Isn n th t nn clastic tell teel spring free I to i Hate Is n pendulum that a n M 1 trat p string Id III a n pendulum etc tte greater the tension and the great rt t ir tr in force Corce of gravity operating on oni i common pendulum the Iho more rapid rill 1 I lit the vibration that length and of the string rod tod f r r i affect the pitch that vibrating oun boards bouM etc elc Into inui or segments nodes and both In sections ju and as os a tl h JI Aft flir deducing th laws of sound the m of or th the human olce Its uti tare cart culture etc should be tak tn n up at first t tv L means of ot experiments exp ntH ih the of ot the children The Tte professor has hili urged that the study stud classes should note anti and fri or to 10 forecast the weather The Ther r fl signal Ignal stations ir art d great real aid In thin Ihl direction anti and publication should hould be In th kinds of the teacher The class voted in t the weather bureau In this Ihl t next week and Or Dr Hyatt IaU has hn furnished for lor the New XelIa h i a storm map together ih b I description of the Iho ordinary wither map mal given herewith DAILY DAIL MAP JP TV n weather luther map Issued dally dall by b the tho thol V l weather bureau and distributed lI to We who ho are Interested li It n I well 11 r publication It the Ma Mai III i i ji 4 which weather dally tit 8 II a m anti and S p m Jr time These observations mst lIt of readings of ot the barometer i ni dry Ir and wet et direction d w ity of ot wind state of f ar jt kind direction of ot the Iho i uis and lind amount of or II no i i are to Washington a ar t many man of ot the weather bureau hureau M the country for fort t atlon allon on maps and II nil bulletin 1 i lines called Isobars art tre drawn points h the name at nt r pre a line I i ir for each of an anI I h II IT IIi the h nf of the I ft rolled railed ron roni r rI i ins I places hiving h hl Ihl same tern f url lire drawn for earh Arh ten de deli li pr t e of e f the thermometer I I tor Heavy He lines line ht a 0 aff ff d ded d change dlan 1 In temperature has hils oc O Orr w rr within the Ih last II t hour Art arc d The of the thes th 1 s 8 Indicated by II an AU arrol flying i the wind l or nr to 10 the or orin in vane The state of nt weather her clear ear partly cloudy loud loudy it ng or lr snowing Is Indicated by II symbol Shaded areas used U IJ show hoI when r ln or snow snows s fallen since Inee the last observation V T l AND D DRY T 11 e temperature of the air as II pub i td d on nn the man U I observed with ft 1 r bulb thermometer A reading of 01 i f P thermometer h that Is III Isi i hose bulb Is I covered with a ing Is also made but not pub The from Irom the wet t ted If Ie the air Is not saturated with moisture In Is mor morl rapid than from the Ih dry dr bulb In to the i Iela l live amount of aqueous vapor 3 por in 11 th thair thair air The difference of 01 b bl tern tween the readings r of these two ther Is I utu U l to 10 compute com putI the Ihl rel live tle humidity of If the nl The rh temperature of ha wet bulb Is Ig lower than Ihan that of the air ah ns OR given Rhen by b the thermometer nn account nf f the Iho evaporation from Irom he bulb The temperature is III sometimes called the sensible len temperature be hr because cause e the em llon of heat h at on the Ih skin agrees more morl closely II with lt It II Indications Indication than with those thoe of the dry ter The map published ith 1111 this represent tho most mo t recent rl n I nd deductions In n to norm torm This Thill Is III not lIot th weather map de above MAP IT OF or Till t STATES The general movement mo ment of storms In Inthe the States Is III from Crom ei fo t 1 to east similar to 10 1 of atmospheric waves an of ot which the Ihl cre 11 are ure designated deEf on the map Highs and the troughs or I 0 The Th highs and 1011 ha hal p an nn average easterly mo ment lIt of about OO mile per day dar High wind lIh rain 01 ell snow ally nil the low area often extend extendIng t tEnd Ing to 10 a 11 distance e of ot BOO miles to the eastward of the of or the storm torm In III advance of ot tic low Jow the winds are gen Joen generally I southerly and consequently con bring high temperature When the of the low lo passes Ia u to the east Iut of 01 tx t place piaN the Ihl wind Ind at lit oneo shifts to th the west WUl or north lIt t bringing ln lower tern tem Souther to easterly winds prevail we e t 1 of ot a 1 neul north aM line passing through the middle of a n high also east of ot a Il like ilkI line pa paIn Ing In through the middle of It a n lot lor Northerly to westerly occur welt of a nearly north and south line past pasting ing through the middle of a low lo also lilo fast east of n similar elm liar one through th Ihl middle of a high The temperature on ona 01 a It given parallel wet west of the low o may mB be he reasonably looked for tor on the Hinn parallel to 10 the pall east when the low lo ha hal passed and will occur along and north of an nil Isotherm of about to 10 de degrees grees rte If It the Is III clear and there ther therIe la Ie but little wind Aiea of low loll pressure ure frequently mow mo to 10 LIt HIP south of th Rock mountains to tn the pl and tin then change direction to tn north of tau east our Ot the eastern half of the country Storms In the of ot Mexico occasionally move to the tho west westor e l lOr I or of I I hilt but alter after reaching the coast coaH they general change di direction nd move mOIe to the northeast northeastward I Iward ward High all move to the th south southeast east a 1 and usually u attended by b fair fairand and cool or cold weather A cold wave U l always accompanied by b a high |
