11-13. America,in Assoc. for ThoraLcicSorger- 40th amnnutal, Miami BeaIch, F-Ia.(H. T. Llne-ton, 7730 CLaronlcielet Ave.,St. LouLIS 5. Nlo.)

11-13. XnIllricainc Ist. of C helimists.Mlinineapolis. Nltinin. (1.. Valn Doren. AIC,6(0 1. 42 St.. Nexx Yor k 17)

1 13-. Intcrmationatl Acetv lene Assoc.,ntita.l. FSettle. X'ash. (1.\AX, 30 W. 42

St., Nexx York 17 )1-1 3. Q(1itotics ittn Flecti-oil Trtan1spOr t.

sx nip. (hy invitation only), I ondcloni. Eni-klnd. (G. F. W. WN'olstenholmiie. Ci;bFVonna(kttion. 41 Pot'tlland I'1.. I ondon. XW.I )

I /-13. Raitc FIaths in Biochetiiicalanind Medicall Rcsctr cih, conf.. Atmes lowlx .(J. Ci. Grlaci. Collcie of Vetcrint rvx Medi-cine. Iowx State UIv.nix .A ncs)

11-14. X\mcricatn Helicoptcr Soc.. an-nnal. M'llilai le;cchi. Fli. ( H. NI. LoLins-hutLiV. -\FHS. Fi-. 64 St.. Nex York 21 )

11-14. Nationl Scicicc FI aitr-ItItc -atiomtial . hidCi ati a polis. ml. ( Science SCe-t

ice. 1719 N St., XX ashinuton 6)12. P)rotein inmd A1i nllO AcidI SLipple-

liletitat ionl. C hiicaco. Ill. [J. I-. Sillme \Soc.of \Vitalmiti C hentists). LxIaporated NlilkAx.soc., 228 Not Iih Lai Salilc St.. Chi-cacto

12-14. Amcticai Assoc. lor C citPalatc Rchaltiltit.tioni. Dcnxcr-. CColo. (1). C.Spriesterslach. LUnixesity 1-ospitals. Ioxx a(-Itx" owxxl)

2 1/4. *\ met Sii lust. ol nld n-lt i.lI IcitiecIIl aIttS iHtal. )aillas, -1-ex. (F. .1. -it-

let-. III. 45 N. [Itch1 St.. ( olnmIllhnls .

Olhio)12-14. V itrinitm .Xc;adl. ol Scienice. IRichl-

mond. ( P. NI. 1Patttersoti. Hollins College,Va. )

13-14. Proctolocical L atin.a. 2nd intern..Rofme. Italv. (Gi. B. I-. Simonetti, Vi;a S.RaItfflec 3. MIillano. Ital )

1 1-8S. Aniericati Soc. of MNtaillo-facial Stir-cons. I os Atigles, Callif. (1- C.Hinds, 1508 MNedicadl TIoxers, Houitoii 25.

1 -1. InterltiationAl College of SLin-geniis. 'th bichieiii conf.. Roitie. Italv.(ICS. 15;16Iakc Sheote Driv e. Chicalgo,,

/ -20. Aeiiiccan WXVter work-s AXssoc..titiLtial Cr11iV.. Niatiii BeCachI. Fla. (H]. V.

Jot dati. XXX XX A. 2 Pat k Ave.. Nexx Yot-k16)

/ 519. Itistitnite of Foodl Icchnologists.20th ;anniilal. San iFrancisco. C alit. (C. S.L txierrcnct, IF-F. 176 W. Adaiis St.. Clii-CagO 3)

1- 2(1. Niatiolltl TLIbuerculosis Assoc.I os Atnelsc1c. C alif. (J. C. Stonec, 179)1Bri oadwxx av Ncxx Yoik 19)/- 1 7. Soictx of Anctircani Nfilitarx

Ln-tincers. nail. conxv.. Waishtlinton. D.((I) X. SIl ix aln. S ANIL'. 140 S. Deal-otornSt.. ( hicico. 11i.)

10-/N. XAmerican Opliathl.l molo]cical Soc..C olor,tlo Sprines. Colo. (NI. C. V'heleit\))XX. 9 St.. Nex Y'oik 19)101--/. Aniieitican TrIoean Soc.. 1 os

Xngelcs. C alit. (FI. W. Webster. 19IB oadxxix \ zNNx\v Ytot k 19)

/ 1(). Atillrl ictl uLologicad AXssocC..C hicigo. ill. (XW. P. DidLnisch. 112'0) N.C'ha1tlres St.. 13a1 til-norc 1, MId.)

16-2(1. XlcdieAl l ibrvx ,\ssoc.. IKjxan.;s,

Citv. M'o. (Nliss N. A. Nlchne. Upiohir Co.Librlr.rv 301 Hentrietta St., Kala1mlazoo.Mili.'l.)16-2/. Americai XAssoc. on Nental

Deficiencx annol.L Bdltimore. MId. (N. A.D)a\ ton. P.O B3ox 5 I, Nlatisfeld Depot,C'otl J

I7- IS. SLopercotidnctixe Technlitiqe folC oiiputitin Sy stenis, s nmp.. WXashington.D.C. (M1iss J. eno, Codle 430A, Office ofN axal Rcsetclirc. WXXshin-eton 25)

l 7-20. Ximerican Assoc. of PlasticSUot eons, Nli lxx anke. XXViS. (T. D. Cirotiiti.661 TrFt.xvis St.. HoLnstoti 25. T1ex.)

1S -/ A(\ricLtta1XL1t1l1tM orology 3rdcmiJf.. Kaisa,is C it. N O. (K. C. Spengler.-Anici cLiln Nleteoroloioical Soc.. 45 BetcotiSt.. BIostoti. Ma,iss.)

8 -20. Sociiety fri I-\ perimentital StressXti.ilx sis. sprinti. Indliatipolis. hid. (XX MI.NioitIVx. SI 'S,\. 1'.0. B3ox 168. CentralScq t Li-c Station, Catbridge 39. Nl ass.)

15-27. Wool Coitf.. ititerlt.. Ha1irrogatca.Yiortkshire. Ltiglatil. (A. XAl. Beitiett. I ex-tile Ilst.. 1() Blackfrtiats St.. Nlatichlester 3.

'/ 22. Societx Ior-FIconomiiic Boittixn 1stmiIntl Laifav ette. Iidl. (Q. o(iies. Nc\eCvOcps Restc crli Birmic. BeltsxilIc. 'NI.)

22. Nlir iland AcXic. ol Scitiices. Balti-moiire. (I. X. I aster MDx in(us Nills. Md.)

22 -6. Xii PollLtion Cot itiol Assoc..1 cI iiitimnal Citincin tiati. Oli'o. (C. W.Ciiet - 024)))) Bieckmiiart St.. Cincii nialiti 14)

22 26. Oil atind GCis Poxer Cnot'.. KamtsasCixt XNlo. f. 1B. XLteDogl(t;l. A.SMI-I. 229XW. 3 St.. Nexx Yorlk 1S)

2 2-" \iA 'ciii SOC. i'OI Q l it !'

-1 I'WI

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SC IENCE \VOl. iii

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I1106

Control, alnnual conv., San Fralncisco,Calif. (W. P. YoungclaLs, Jr., ASQC, 161W. Wisconsin Ave., Milwaukee 3, Wis.)

23-25. National Telemetering Conf.,Santa Monica, Calif. (A. F. Denham,American Rocket Soc., 925 Book Bldg.,Detroit 26, Mich.)

23-25. Technical Assoc. of the Paperand Pulp Industry, Chicago, Ill. (J. Win-chester, TAPPI, 155 E. 44 St., NewYork 17)

23-26. Design Engineering Conf., NewYork, N.Y. (D. B. MacDougall, ASME,29 W. 39 St., New York- 18)

23-28. American College of Cardiology,9th annual conv., Indianapolis, Ind. (G. F.Greco. ACC, 114-08 Linden Blvd., Ozone["ark 16, N.Y.)

23-28. InstruLments, Electronics, andAtutomation Exhibition, Olympia, London,I- ngland. (Industr-ial Exhibitions Ltd., 9Argyll St., London, W.], England)

23-28. International Ceramic Cong.,7th, Great Britain. (G. N. Hodson, Or-granizing Council, c/o Hathernware Ltd.,Loughborough, England)

23-28. International War ProphylaxisCong. for Physicians, Noordwijk ann Zee,Netherlands. (M. Knap, 46 Schubertstraat,Amsterdam, Netherlands)

25-26. Refractory Metals and Alloys,symp., Detroit, Mich. (E. 0. Kirkendall,AIIE, 29 W. 39 St., New York 18)

25-5. International Federation forHousing and Town Planlning, cong., PuertoRico. (IFHTP, P'ark Hotel, Molenstraat-53, The Hague, Netherlands)

26-27. Psychophysiological Aspects ofSpace Flight (School of Aviation Medicine,USAF Aerospace Medical Center), symp.,San Antonio, Tex. (J. Harmon, SouthwestResearch Inst., 8500 Culebra Rd., SanAntonio 6)

26-28. Society of Naval Architectsand Marine Engineers, spring, Washington,D.C. (W. N. Landers, SNAME, 74 TrinityP1., New York 6)

29-2. Chemical Inst. of Canada, 43rdannual conf., Montreal, Quebec, Canada.(CIC, 18 Rideau St., Ottawa, Ontario,Canada)

29-4. American Soc. for HorticUlturalScience, 8th annual of Caribbean Region,San Juan, PuLerto Rico. (E. H. CJisseres,Londres 40, O.E.E., Mexico 6, D.F.)

29-5. International Commission onIrrigation and Drainage, 4th cong., Ma-drid, Spain. (D. Diaz-Ambrona, Comit6Nacional Espafiol, c/o Ministerio de ObrasPtblicas, Agustin de Bethencourt, 4, Ma-drid, Spain)

30-1. American Gynecological Soc.,Williamsburg, Va. (A. A. Miarchetti.Georgetown Univ. Hospital, Washington 7)

30-2. American Orthopaedic Assoc.,Hot Springs, Va. (L. R. Straub, 535 E. 70St., New York 21)

30-3. Asian-Pacific Cong. of Cardi-ology, 2nd, Melbourne, Australia. (A. E.Doyle, Alfred Hospital, Melbourne, S.I,Victoria, Australia)

30-3. Fibre Science, annual conf.,London, England. (A. W. Bennett, TextileInst., 10 Blackfriars St., Manchester 3,England)

30-4. Reactivity of Solids, 4th intern.symp., Amsterdam, Netherlands. (Ir. G.van Gijn, Secretary, 4th Intern. Symp. onthe Reactivity of Solids, Technisch Hoge-school, Eindhoven, Netherlands)15 APRIL 1960

a pure tritiated L-amino acidat less cost than C14- labeled forms

TRITIATED 1-HISTIDINEvithl this newu compound you can save valuable experimental timle because:1. Absence of 1)-form eliminates background interference in radioautograp)l1s.2. You get high specific activity... 1.7 curies per millimole.3. The compound is radiochemically pLre as determined by chromatography

and isotope dilution.4. Stereo specificity is clhecked enzymatically.

c$e mon c), too-sernd uis your requirerments, ard w-e will he happ) to glie you oiurlow prices. Jie also suIup)ly Tritiated Tymidiinc atid a lost of ot/er radiochemicalsan(1 bioc/hemzicals. Senzd for your free col)y of ouir ne!ly) relised price list.

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1107

June

/-3. Instr urriceritall Miethods of Anals si.s.an nual 'symp. NMontreal. QubheC. C anada.(NA. H. KuIslinick. InIIstrunIMenIIt SOC. OtAmerica, 3 13 Sixth vx .. Pittsburgh_ 22,

I S. Irrigation antd Drailnag,e, 4thi Inter n.cong., Madrid, Spain. (DI. Diaz-Amb-rona,( omit6 Nacionil Ls,panol dle Ia C omiiiroiInternlationral dle Riegos v Dr-enajes, iNlinis-teri-o De Obhras PuliICaIS, AguLStin Dc.1BCth enCOUrt 4. Miadhrid)

2-4. Amer c~an A\ssoc. of' Blioanmalysts LandC a Iifornia A\ssoc. of C llicatl La,bor atonecs.annual,1, San Fri ancisco. C alif. (Mrs. NI. K.I lig-ins, 75~Buecna V,ista Asve.. San FI-ian-cisCo) 17,Cai.

2-4. Drug,s Afiectin, Lipidl 'Metabolism,Intcrni. sxnlip., MIikian. Italys. (S. G araltr ni,c/o Institute ot Phar miiacologsv. Via declSat -to 2 1, ~Milan, Itailv

3.an uieican Niedical Wome'Alliance. 7thi cong.. S~an JuIan. Pulerto RICO.(NIrs. S. D. Roseki-ans, S504 Newset St.,NNullSV, Ie1, WXis.)

-5 N. Specild L ibi laries Assoc., 5 1st an-trUal, CIlesC]land, Ohio. (B. NI. Woods, SF A,31 L. 1(1 .St.. Ness York 3)

5-9. Amer can Soc. of' NifechaL-nical En-g ineers, SLrIImeICI LannuaMl and Iasviation couif..D)allas, ITex. (I S. Derrregar. ASNIF, 29W. 39 St., New Yor-k 18)

-5-9. Worild Poswer C oufl.. Madrid. Spain.(D. J. Perez, Pozula1o, Spanish NationalCorinriittee, Generlal Pardinas. 5Si, NMadrid.Spa in)

5-10. Nationall C onf. oni Socia,l Welfare,

annl-ual. Atlantic C its. N.JI. (NatI. C onf.oni Social Welfarc. 221 Wes,t (hiv Sr..CoIluimbuIS I 5 Ohio)

5r /4. XXV C'oldi Sprring Harbor Ss np.Oin Qulantitatisve Biology C'oldi Spririgi Ia-fabor-, NA'n. (A. C hos-nick. Bioloc,ica ILab-oraorsv, ILorig lslaridl Biological A5.ssoc.,Cold Springl H.arbor)

6-/O). Inter national C orif. oni Lisvc Plolio-sirus VaCCineCs. WashingtOon, D.C. (Seer cetar at, Pan AnXriircan H ealtli Or-can naion,, Wor ld H caltli Organ izatiori, SONess, Hlaripshi rr eAs c.. NW, Washlrgoril

7-11. NI crossas c Tutbes, interc ri. c(in,-,.Mnlrrich. Gcrriaris. lNIachiricteritechinischeGeSel ischaft iri VDLF N,TCG). Frariki l-rtmManNlair, Osthiafenpl'atz 6, Ger roans)7-13. Dosrriieltr s in Health Pb11ssrs.

Ss nII p.. NVre riria, A Liust r- at. (Inrternartiorial\toriic I riergs- A\gncsv. KLir ritricr Rrricr.NI IrIaII IALStr a~

7-1IS. Par tral Differential Fqriatioois aridC ontiritruriii Nleehnariics, interni. corif.. N'Ladison. Wis. R. IF. Lariger NIatliemiatics Recsealrcli C enter. U.5. Armiis, Uriis. otl XXVislco(isisri, Nladci~oni (a)

N 9. Seleniuriil in Nultr itiori, COrif.. ltIthCa,N.Y. (K. C. BJeesoni, U.S. Plant, Soil], andNuitr it ion LI ibor ators Ithacat, N.Yr.)

5N 10. Cariadran F-ederatiori of Biolo,lcicaSocieties (C ariadiaril Plivssiological So.Pliarmtiacological Soc. of' Caniada. C anadMianAssoc. of Aniatomiists, Catiadiari Blioclieriiiiclal Soc.). 3rd annMirl Winnipeg. Mlan toba.(I-. H-. Benslev Montreal General Hospital.16-50 C edar Asve.. \Montreal 2~. 1),Q,)

8N 11. National Soc. of Professional IFri

,zrer,annull~, Bioston. NMass. (P. IfIRZoblhIiri s. NSPI-, 2029 K Sr., NW. Wash-igtori 6)N 1.\nier can C ollege of' Chest Pbsv

sician.rr Miarii Beach. Fla. (NI. Kor-tifeldt.11 21. CIheStriuLt Sr.. C hicago I 1, Ill.)

9 /f). Xriicrican Gcir tiarrcs Soc.. NliariiBechil. Fla. (RZ. J. Kral-erier 290(7 Post Rd(..Warswick. R.I.)

V- 1/. AeouIStical SOC. Of .\ie c,Pr-Osdecnce, R.I. (W. WXaterflall. A\S\. 335 E. 45Sr.. Ness 'Yor-k 17)9 E1. nrdoertiec Soc.. Nliarii Beaich.

Yi(. I-I. H. Tun tier. 20I N. WValker, Okkialiorii (its 3. Okla.)

91.N ation.rl Spe)lceolo ,cal Soc.. an-nuLI'. ( anrIsad. N.MX. (Gi. WX. Nloorce. U.S.Geological Sur s es\. Nlerilo Park. Cailif.)

1 2. Ariier canl INledlicail Woriens"'\Asoe.. NMiari iicBach. F- a. (Mrs. L. T1NEiaalls\. 1790( Br oadss as. Ness 'nor k 19.Nt.

9-/2. Ariier canl Rlicumlar isrii ANssoc.. anlmi,tl. Holls ssoodl bs the Sea, FLa. (F. I-:D)riiartirun. Pr esbsvter an H-ospitil. 622 XV.168 Sr.. Ness York 32)-

9-12. Amriincain Thirrapeuric Soc., Mliamiillecich Fla. (C). B1. HunJter., Jr-.. 915 19 St..NW. Waishirgtori (a)

1(0-12. Amier can Collcize of' A\ngiology.NII.iaui Becach. Fl,i. N. Hadpcr n, 11 Hatirip-tori ( ourt, CGreal Neck, N.Y.)

/0 /2. A.Xlriercan IElectroenceplialo-raphic Soc., Biostoni, Mass. (G. A. Ulctt.1421 Grtatten St.. St. Loui1s 4. No.)

11) 12. Societs f'or Biological PsycliiatrysMliarmi Beach. Fla. (G. N. IThomipson. 2(11(\VN Ish ire Blsvd.. 1 os Angelecs 57, C alif'.)

GILLINGS-BRONWILL

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SCIENCE, VOL. 131