D eaf M ade to “H ear” Through F inger Tips Events in the Lives of Little Men THE FEATHERHEADS Felix Loves the Little Dears T h e discovery th a t th e hum an skin's ability to detect rapid vlhra tlons Is much g re a te r th an has pre- vlcusly been supposed has been m ade by Dr. Robert II. G ault, d irec to r o f th e vibro-tactlle research laboratory of Sm ith college. Doctor G ault hus been engaged for several y e ars In ex­ perim ents to enable the d eaf to hear through th e ir linger tip s by touching C o m p e n s a te * f o r L oss o f E n ­ a telephone receiver. Previously scl e n lists have supposed th a t a vibra­ e rg y C a u s e d b y th e D e ­ tion fa ster thun l.fidd tim es a second w as too fast to be detected hy the te c to r T u b e . skin. According to D octor G ault, how­ ever, these touch organs can detect P roperly designed radio frequency v ibrations as fast a s 2,700 a second. in ip litie rs contrbute not only to sen­ T hough m any of th e vibratio n s of the sitivity of a receiving set bui ulso to voice a re m ore rapid th an this, “oo,” >ts tone quality, according to resu lts for instance, as pronounced by the obtained from a se ries of te s ts con­ average m ale voice being about 3,800 ducted in one of the lab o rato ries of a second, and "ah " 3.682. D octor G ault a large radio com pany. says th a t if th e skin can receive vi­ T he function of a high frequency b ratio n s as rapid a s 2,700, It Is am ply am plifier in the la tte r re u se may be sensitive to u n d e rstan d s|>eech. T he difficult to com prehend a t first, since, discovery w as m ade w ith an In stru ­ according to theory, it is credited m ent called the “ te le ta c to r,” designed only w ith am plification of very weak and built for his use by the Bell tele­ signals to a point w here they ure of phone lab o ra to rie s in New York city sufficient intensity to o p e rate the d e ­ tector tube. To u nderstand the m an­ H is Position ner in w hich an r. f. am plifier im ­ Gap Johnson w as trying to back proves q uality, a study of the func­ aw ay from the -crossroads sto re with tion of the detector tube will be found many yanks at th e reins and num er­ useful. ous yells and oaths. Ills d a u g h te r In effect, a detector tube Is really a sprang from the wagon and began “distortion" device since it is by dis beating the m ules over the head with tortlng one-half the incom ing rudlo a club. frequency w ave th u t the signal is “ Why don't you buy an autum n ! m ade audible. T h e disto rtio n of tills bile?" usked a salesm an who had a r . incoming wave is accom plished by o p rived during the operation. "It would cratin g the d etecto r tube ut grid and save you a lot of trouble." plate voltage values w here a slight "I'm usen to th e — p ’tu I— trouble.' positive cliurge will result In an ab was the reply. "I know how to handle norm al plute c u rre n t und a negative these devilish m ules and I w ouldn’t charged subnorm al p late c u rre n t with know how to m anage a c a r " respect to the effect of sim ilar churges “ Well, it might save the young lady on the grid if the tube w ere 0|>eruted a lot of unnecessary ex ercise ' on the “stra ig h t" p a rt o f Its grid volts “ Aw she's going to get m arrleu —p late cu rre n t c h a ra c te ristic curve. p r e tty soon an d needs the experience | Thus, the incom ing w ave train , hav- In m anaging a husband. Hud up. , ing positive and uegative alte rn a tio n s, the re, m u les!"—K ansas City S tar. will be re p re se n tad in the p late c ir­ cuit in the form of abnorm al plute H eadach es fro m S lig h t Colds , cu rre n t fur th e negative half and It | L a x a tiv e BROMO QUININE] T a b le ts re- Is this difference of p late c u rre n t val- I lle v e (h e H e a d a ch e hy c u r in g th e ('old. I/Odk for s ig n a tu r e o f E. W . G rove on ue th a t causes an audible sound in j th e box. 30c.— Adv. the phones. Since it la only the difference be­ A P la n t Puncture» T ire» tween the d isto rte d poeltive und neg W ur (*< mt hi tied ngniiiKl the “p u n c I ative hulf cycles th a t Is responsible J (lire weed. t ’ulifi»rni>i'H rapid »prcud for reproduction, It is evident th at mu vine whose h alf inch thorns plin much of the signal stre n g th Is lost in I imvoc with m otor cur tire s on couji (lie process— the low er h a lf of tl»e r.v mud». A single vine found n«*»r » u v e entirely m issing, plus th a t p a rt 1 Los Angelos covered m circle 14 feel of the upper h a lf lost through the hosperH te efforts to check oppoalng effect of the d isto rted lower ! icross (his troublesom e plant'» sp read ure j half. For th is reason, weak signals ■ lilndered h.v Its prolific seed. ..NRI to m ust tie am plified before detection, if i M pm re fo o t, t . • t im iture »11 year results of any kind a re desired. round tiud force » continuous hit I H e.— In the audio frequency end of the Popular Science Monthly. receiver it is found th a t, due to in- i ertlu of reproducing m echunlsm s, ttie i a ir and, lust but not least, the de- I tecto r tube, considerable energy is re ­ quired to reproduce faithfully m uslcnl - W as Y ou r tones In the lower register. G ra n d m o th e r’s R e m e d y Pow erful audio am plification will F o r every stom ach overcom e the effect on Inertia of a ir i und in te stin al ill. and reproducing m echanism s, but It i T h is good old fash* cannot com pensate for th e loss of eu % loned h erb home ergy caused hy the d etecto r tube. ■ rem edy fo r ronstl- T he only remedy for th is Is ampUO- ajgjfr potion, Rtomach Ills cation before detection. T hus the ra ­ •r* a n d o th er derange­ dio frequency am plifier com es Into Its m ents of th e sy it­ own us a c o n trib u to r to good audio reproduction, und the m ore well de­ em so p revalent th ese day s 1» In even signed stag es ahead of the detector 're n te r fav o r a» a fam ily m edicine bun in yotir g ra n d m o th er's day. th e b e tte r the quality ut th e output of the set. T h ere Is one draw back, F o rb id d e n to T rtm B e a rd however, In m ultistage radio fre­ A h is to ry o f th e ris e and fu ll o f the quency am plification, und th is Is due to pickup ant* in te rsta g e coupling be­ »card w o u ld m a ke In te re s t Ing read ng P erh aps th e firs t re fe re n c e to tw een various colls in the receiver ti< h fa c ia l n d o n im e n ts Is < PR|T e $150 AT y0UR DRUG STORE I o f Krw m ola aktn bleach w ill co ivtn r« the w d tra n sfo rm e rs w as conclusively deni- i ah ep llc al A lso enrew ♦•«•*», a. Prien | ] ft. A *« adik fa r Sample »«r d e a le r ItoaiH y florifelct Free I n C, II. o n stra te d In a series of ex p erim en ts | £ •rry tk».. Dept. M. fctfl M ichigan A » e .tk i« w g o "KOENIG MEDICINE CO. conducted at the Zetka lab o rato ries [ 1045 N WELLS ST. CHICAGO ILL. | W N U , P O R T L A N D , NO 51 1927. w ith some of th e ir low ou tp u t Imped- 1 a nee tubes. A th o u g h t it*»*« m » n k ite » m lot o f Good quality radio am plification 1 T alk may be a g<»»