Carrolltown High School - Echoes Yearbok (Carrolltown, PA)

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14ri oioi Dedicated to OUR PARENTS and OUR CFEACHERS x

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Y, 1935 SENIOR CLASS ECHOES PAGE TWELVE SCIENCE OF TODA Y wmr no RADIO Pnooniuis soma- 'nnms FADE. At some time or other almost every member of the radio broadcasting' au- diencg has experienced the annoying phenomenon of fading or mushing of a radio program to which he is lis- tening When this occurs to the DFG- grams: from a broadcasting station many miles away, most listeners ac- cept the distortion as one Of the 1121U11 - al results of broadcasting over long distances Under certain conditions, however, fand only at nightl fading and mush- ingn are experienced by listeners with- in thirty or forty miles of the trans- mitter, T-he responsibility, however, ,rests upon a mysterious electrical cloud in the Sf.l'2lt0SDhEl'6. To explain this, the different waves must be de- scribed that carry the radio program from the broadcasting station to the home. Radio waves in their journey fl'0l11 the transmitter to the receiver may travel over one, two or more paths simultaneously. There is, first of all, the so--called ground wave, which travels directly over the surface of the earth from the transmitter to- the re- ceiver. It is this wave that serves tlhe pri- rnary listening area of a radio broad- casting station. Its transmission is unaffected by any seasonal -conditions and it is -of the same intensity during both the day and night. The useful range of the ground ware depends up- on the power of 'the transmitter, the frequency upon which it is operating, the nature of the intervening land, the conditions at. and the sensitivity of, the radio set in the home. The next wave is the sky wave. Be- cause of many obstructions usually found in the path of the ground waves over the surfaces of the earth. Long distance transmission, therefore, depends upon the sky wave. The sky Wave upon leaving the trans- mitter, travels upwards with little at- tenuation until it reaches the Ken!! nelly-Heaviside layer, seventy or so miles above the earth. This layer, com- posed of f-ree electrons Cinfinitely small particles of ele-ctricityj acts as an electrical mirror. The sky waves are reflected by this mirror and are returned to the earth. The point at which the waves -are -re- turned to the earth is usually many miles from the transmitter. Because of the more or less unobstructed path the wave has followed, through the upper air, the strength of the received signal may, at-times, reach very great intensities. The Kennelly - Heaviside layer, however, does not have well de- fined, fixed surfaces. It is, on the contrary, very much in the nature of a, tremendous cloud of free electrons which, like the Visible. moisture laden clouds we see close to the earth, is con- tinually moving, shifting, drifting. and changing shape. I During the day time, the nature of this cloud is such that it cannot re- flect the-waves in the broadcasting frequency. For this reason, no fading effects on broadcast transmissio-n man- ifest themselves during the day light hours, Olnly direct ground waves from the broadcast station reach the listener and no fading or 'tlllushillgv disturbs the quality of the program. At night, however, conditions of the upper atmosphere are favorable for re- fraction of the radio waves of broad- cast frequencies. But because of con- tinual movement of the Kennelly-Hea- viside layer, i-ts virtues as a. mirror are, to say the least, uneven. As a re- sult, the sky wave itself, returning from its contact with this rolling sur- face, is subject to a great deal of vari- ation ori fading. At times, the ground wave and a sky wave arrivie a-t the receiving. point after having traveled over two paths of different lengths. The two waves do not, therefore, arrive at precisely the same instant and are -said to be out of phase. Under these condi- tions fading or 'fmushingn or any number of odd effects, may occur to the irritation of the broadcast listen- ers and of the broadcast station en- gineering staff. This phenomenon which usually man- ifests itself at distance-s greater than fifty or more miles from the trasmit- ter, and never in the daytime, is some- times di-sag-reeably evident to listen- ers relatively -olose to the trasmltter. At night -time, during certain seasons of the year, these fading effects are unusually prominent. Under these con- ditions, listeners in a metropolitan area. served by high-powered transmitters, are apt to suspect the management of the broadcasting station of faulty op- exiation. Trhe unfavorable resul-ts, how- ever, are caused by the admixture -of the. sky and the Ugroundi' waves- at the receiving points, which may be many miles from the transmitter. All broadcasting stations have cer- tain areas wherein UlllllShll'lg,' of the signal occurs at night and these areas change with the seasons of -the year and various other factors. Strenuous efforts are being made to overcome sucih effects, which, of course, curt-ail the -service area of a station to some degree. 1 But it is not an easy matter to deal with invisible waves traveling through an invisible, inaccessible cloud of elec- trons, many miles above the earth. ' Paul Sharbaugh, '35. BACTERJA. Are bac-teria the friends or enemies of mankind? At first thought, recalling our gen- eral association of bacteria with dis- ease, one is likely to class microbes as our very definite enemies. To-day, the exact contrary is known to every bacteriologist. Research stu- dents ln the bacteriological laborator- ies of Drexel Institute, Philadelphia., know that the bacteria have gone into business--big business-and that they are nourished and pampered for the Work that they do. A check by associates ln the depart- ment of Biological Sciences at Drexel Institute shows that bacteriologists U10Ughout the world have isolated and classified more than one thousand' different kinds of bacteria. Seventy- five per cent of this number are defi- nitely beneficial. O-nly ten per cent produce disease in human beings, and only three per cent produce diseases in t-he lower animals th-at are transe- mittable to man. 'lien per cent produce disease in plants and two per cent pro- duce disease in the lower animals on- ly. Dr. Walter L. Obold, professor of Bi- ological Sciences at Drexel Institute, and author of a number of important publications, on bacteria and allied sulb- jects, in discussing the subject, said that bacteria are now recognized by industry as the allies of man. Many years ago Pasteur recognized the part that yeasts play in the man- ufacture of alcohol from sugar in the wine industry of France , he said. In spite of the fact the tfhe microbes were not originally associated with- the dis- ease, whenever the name bacteria. is mentioned, typhoid, scarlet fever, and diphtheria immediately come to mind. The beneficial activity of 'bacteria is such a. common oocurence that it is frequently overlooked. Ther production of vinegar from fruit juices is caused by a sausage- shaped bacterium resembling the type of microbe used in the production of sour milks, such as gioddu in Sardin- ia, koumiss in Russia, kefir in the Caucasus, leben in Egypt, yogurt -or mazun in the Balkans, and acidophilus in the United States. Sauerkraut is produced by the same group of bacter- ia. Many of the common cheeses are produced from pasteurized milk inocu. lated with 'starter cultures' of spheri- cal bacteria occurring in long chains. Within the past few years there has been an increase in the nu-mber of quick drying paints- and varnislhes on the market which depend- upon a. sol- vent known as butyl alcohol. It is produced by fermenting corn with a, rod-shaped bacteriom. The same mi- cro-organism produces acetone which is used' in the manufacture of smoke- less powder, artificial silk, and the dope for aeroplane wings. Every modern dairy farmer has 9. silo in which bacteria ferment and pre- serve the vegetable matter coinmo-nlg called ensilage. Industrially bacteria aid in the sep- aration of ,vegetable oils and in the ferinentati-on of rubber latex. The bac- te-ria in the soil aid in the purification nf sewage wastes and in the enrich- ment of the nitrogen content of the soil so that green plants can gr-ow and supply mankind with an adequate sup- ply of vegetavblesf grains, and fruits, Other bacteria aid! in the fermentation of coffee and cacao beans and in the curing of tobacco. '! X'4'4 X'4'4 !'4 !'4'4 I !f'P4'4 ! F'!'4 I'4 ! P4' COMPLIMENTS or P. J. WEBER

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1935 SENIOR CL-ASS ECHOES PAGE FOURTEEN 0 RPATROVIZE OUR ADVERTISERS O j '!g! P'P'! X'4 Z !'4 ! P'!'4 ! I'4 P'P'I P4'I P'! i -Mw!0!-'z-4-'x--'--:--x--x-z-4-4-':0!f+-t-'2-4-4-M'-xw1-'t- '! ! !-'I-'!f'! ! !v'! !-'! H I-'!-'l l ! ! I- A if . 5 - i. E Compliments of 'Y' C0mP11mG11tS Of Compliments of V 4. S T 0 L Z B R O S . SCANLAN'S CONFEC- if E A FRIEND Z Meat Market TIONERY . 'I' M,,,,,,,,,,!,,,,H,,,,,M,,,.,,,,,.,,,,,,H.,,,,,,,,,,,.,,, +'z--x--x--z--zf4-z-:-:-1-4--x-4--x--:-4-z-4--x--!--:--M -x--z--:-z--z--z-M--:-x'4-+-!-xw:-4w!-4-!--2+'z--z-t--z' Compliments of Compliments of Compliments of MA.RIE,S BEAUTY E ,I P. L. ECK 8: SON . SHOPPE RAY FARABAUGH . '1 I H 2 1'4'!'4 1'4 1'f!'4 1 ! ! ! ! f 1 1 1' s-z-fx--z--z--z-4-z-x-:-x-+-x-40x-4-:--x-x-+-x-x--z--x-4 -z'-z-zf+-x--z+-x-z--z-z-4-x-+4-z-4--x-4-+-z-x-4-:-x- G0mD1im9UtS Of Compliments of C0mD1iH1611'fS of A 5 E A FRIEND E W. A. ECKENRODE FRED J- FEES. . M--!--!w!-4-4u!0!'-!--!'-1--z-4-z0:--z-x--x--:--x--r-4--!- ,,!,,x,,,,,x,,,,,M,,,,M,,,,,,,.,,.,,.,1.,.,,..,,,,,,,..!..,. g4-4--z-4-'zvz-fx-4--xf-z-4-z-z--x--:-1+-x0x.-x.-z-4.-M-4- , -2- A . 5 s , Gomphments of 33 Compliments of ComP11H1611l3S of 1 E 0- F- STOLZ 1 E E MIKE FARABAUGH .P R. J .WENTZ HOTEL 'L is E E4'1 ! ! 4 W P40P'!'4 1 2'4 1 !'4 f f'4'4'g!,g ' -z-4-z.4--x-4--z--:-4-x--:-x-x-.z-'x-x-40x-40x-z-z-z--r- -:Q-x-4--z-z-+-:-x-4--:-'x-4-z-'x-4-4--x--z--z-x'4-e--x-z- Zi! 33 -1- ' o 1' t f 'I' E . i E omp lmen S O Zi: E C0mP11meHtS Of Compliments of Z? N A MALLOY Q gg HARRY L. FEES E I ' . zzz: Bakerton, Pa. W- D- WETZEL A n M++++++++++.MM0M++++++g --z--x0!--z--M--:--x-4-4-4-'x-4--x--x-4-'M--!-4--x-'x--:--x- g4'-!--1--:-4-4--!--x'4-'x--x-z--x--x-40:--x-4--M0x01--!-'x- 1 'X' -1- M' F' DURKIN E E HARELRQERR E 2 Compliments of 3 E INSURANCE. AGENT 4- e 1 2 3: 52 Ba1'neS 1 ' Phone 55'W E ELMER M. LUTHER ff E 3: Barnesboro, . Pg. Iii f-:-4wx-'z-4w:f-xQ4'-x-1-+40x--z-f:-'1--zwz0z--z--z'-:--xf4-E +M,.!,,M,,:,,!,,!,,I,,H,,,,,M,4,!,,z,z,,,,,,,z,,,,,.i MM++M+M.M.M++++++M0E 2 - W. R. STICH Comphments of E 3 ' 32 Compliments of Z5 N E o N s I G N s 33 ' R. A. 22 3: Spangler, Pa, 'P'!'4 X ! !'4'6 N'4 !0l'4'4'4'4 2 ! Z0! ! ! ! MM '4'5!'4-P4 ! I 10P'P'M P'l'4 P4 l-4 ! l l !'4 P'!' W. EARL SHARBAUGH A E 4-+4-z-z--xwz-z-z-x-+-xf-z-+-M-4nzf-x--z--:-z-z-4-xwz1