- WIL-W - Science...HOTEL RESERVATIONS AAAS CENTENNIAL CELEBRATION September 13-17, 1948 HOTEL LOCATION RATES SINGLE DOUBLE AMBASSADOR 14th and KSts, NW $3.50-8.00 $6.00-8.00 ANNAPOLIS

- WIL-WThe third edition of a distinguished and popular

textbook of geology coming soon!

PHYSICAL GEOLOGYThird Edition

By Chester R. Longwell, Henry Barnard Davis Professor of Geology;Adolph Knopf, Sterling Professor of Geology;and Richard F. Flint, Professor of Geology;

all at Yale University.

The fine qualities that are demanded of a textbook by professors and in-structors are incorporated in the third edition of Physical Geology. Intheir unceasing efforts to improve the book the trio of experts who wroteit have analyzed its teaching value critically. They have evaluated thesuggestions and criticisms of users of the book objectively. Where prac-tical they have changed arrangement or altered text matter to make it assuitable as possible for instruction.

GOOD BEFORE! BETTER NOW!

Besides adding a new chapter, "The Method and Scope of Geologic Study,"the authors have reorganized much of the text matter and introduced im-portant new concepts and ideas. Interesting data on recent geologic oc-currences, such as the history and story of behavior of the new volcano,Paricutin, are given. Illustrative material has been revamped extensively,and new illustrations have been added to swell the already generous collec-tion of pictures.

POPULAR FEATURES OF EARLIEREDITIONS RETAINED

Weathering treated as a unit subject. * Importance of climate in determin-ing soil types stressed. * Separate chapter to cover wind and erosion.Chapter on earth's interior considers modern research in seismology. * Def-initions and elementary descriptions of minerals and rocks covered in thetext proper gathered together in appendixes.

Ready in September 602 pages 365 illus. $5.00

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SCIENCE, August 27, 1948, Vol. 108 9

HOTEL RESERVATIONSAAAS CENTENNIAL CELEBRATION

September 13-17, 1948

HOTEL LOCATION RATESSINGLE DOUBLE

AMBASSADOR 14th and K Sts, NW $3.50-8.00 $6.00-8.00ANNAPOLIS 12th and H Sts, NW 3.560-.00 5.00-8.00BLACKSTONX 1016 17th St, NW 6.00-BURLINGTON 1120 Vermont Aye, NW 3.50-5.00 5.50-8.00CARLTON 16th and K Sts, NW 9.00-11.00CARROLL ARMS 1st and C Sts, NE 4.00-.00 6.00-8.00COMMODORE North Capitol at F 3.50-4.50 5.00-7.00CONTINENTAL North Capitol at E 4.00-6.00 6.00-8.00DODGE North Capitol at E 4.00-6.00 6.00-9.00FAIRFAX 21st and Mas. Ave. NW 5.00- 7.00-8.00HAMILTON 14th and K Stas, NW 3.50-6.0 6.50-9.00HARRINGTON 11th and E Sts, NW 3.00-4.00 5.00-8.50HAY-ADAMS 16th and H Sts, NW 4.00-.50 6.00-9,00LAPAYETTE 16th and Eye Sts, NW 4.00-6.00 6.00-9.00MARTINIQUE 16th and M Ste, NW 3.50-.00 5.00-8.00MAYFLOWER Connecticut Avenue 5.50-10.00 8.50-15.00NATIONAL 1808 Eye St, NW 2.50-3.50 4.50-5.50NEW COLONIAL 15th and M Sts, NW 3.50-5.00 6.50-9.00PLAZA 331 lit St, NE 3.50-4.50 5.50-8.00RALEIGH 12th and Penn. Ave, NW 4.506.50 6.50-11.00ROGER SMITH 18th and Penn. Ave, NW 3.50-6.00 5.50-8.00SHERATON 15th and L Sta, NW 6.50-9.00SHOREHAM 2500 Calvert St, NW 6.00-7.00 8.00-10.00STATLER 16th and K Sts, NW 4.50-10.50 8.00-13.00TWENTY-FOUR HUNDRED 2400 16th St, NW 4.005.50 8.009.00WARDMAN PARK 2660 Woodley Road, NW 4.50-6.00 7.00-9.00WASHINGTON 15th and Penn. Ave, NW 4.50-8.50 8.00-13.00WILIJARID 14th and Penn. Ave, NW 4.50-8.00 6.00-11.00

Mail this HOTEL RESERVATION BLANK to the Housing Bureau(plea.. do sot send to hotel)

AAAS Housing Bureau204 Evening Star BuildingWashington 4, D. C.

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Single room R................. ate__Double room ........ . . ........... RRate

Please reserve accommodations for mysl andthe guests whose names are:

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Rooms will be assigned and confirmed in order of receipt of reservation

SCIENCE, August 27, 1948, Vol. 19810

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SCIENCE, August 27, 1948, Vol. 108

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Register Nowfor A.A.A.S.

WHAT, WHEN, WHERE, and HOW TO GETTHERE:-questions about -seions of the Centennial Meeting inWashington, September 13-17, will be answered completely in the

1848-1948 Gmural Program. To be ure of having the answers m advane, sothat you may plan which sessions to attend and otherwise make themost of your time in Washington, register now for the meeting inSeptember.

The General Program and informative publications about W ion will be mailed toadvance registrants in mid-August. The Program will list the speakers, the titles of theipapers and the location of each session and special event. In addition, it will contaI In-formation about hotels, transportation, eating facilities, messenger servie, lost and foundarrangements, and points of interest to the historicaly-minded as well as to tho interested Incientifc research and its administration in the nation's capital Moreover, the GeealProgram will be a treasured memento of one of the outstanding events in the history oforganized science in America.

In order that you may plan in advance your schedule of activities during the ntealCelebration, please 11fl in the registration blank below and send it, together wh your cheekor money order for the correct fee, to the A A. Administrative Ofices, 1515 Massaehu-setts Avenue, N.W., Washington 5, D. C. (Your convention address may be filled in latw.)This information will be placed on file in the Visible Directory to be located in the StatlerHotel during the meetings, where it will be easily accesible for quick inspection. Findingyour friends and having them Md you will be no problem if you and they hav registered.For your convenience addresses of friends may be obtained by calling EX.. 1000 ad gfor the A.A.A.S. Visible Directory.

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SCIENCE, August 27,, 19^4 Vo. 106

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Personnel Placement

POSITIONS WANTED

Bacteriologist: woman, M.S. research experience, desires researchor teaching position in Philadelphia. Available October first.Box 431A, SCIENCE. 9-3

Biologist-Entomologist, 17 years teaching experience, 5 yearstechnical-administrative-writing in international field. Foreignservice Latin America-Europe. Speaks Spanish, AgriculturalExperience. Available September for teaching or administrativepost. General biology, invertebrate, entomology. Extensionwork considered. Has held responsible administrative post. Box430A, SCIENCE. 8-27

Physician: Veteran, extensive clinical experience (Anesthesiology,Surgery, Gynecology, VD) interested in research, desires assistant-ship in Physiology, Pharmacology or Clinical Research. Box437A, SCIENCE. X

Young physician, B.S.} Ph.D., M.D., Middle Western university;is available for academic position in biochemistry; although willingto assist in teaching program, chief interest is biochemistry re-search, in which field he has had extensive graduate training; forfurther information, please write Burneice Larson, Director. Medi-cal Bureau, Palmolive Building, Chicago 11. X

POSITIONS OPEN

Anatomist, Ph.D. or M.D. Instructor to assist in teaching grosshuman anatomy and to undertake research. University MedicalSchool, West Coast. Box 435A, SCIENCE. 8-27

Biometrician or Statistician: Foif assignment bay area southernLouisiana. Need persons skilled in compiling and coordinatingdata. Experience in writing or in marine Aield work advantageous.Write Box B.F.E., College Station, Texas. X

College Teachers Wanted: Small Christian College in MetropolitanArea. Professor of Psychology, Ph.D., $4000. Instructor inMathemallcsPhysics. Recent graduate with Master's Degree, whodesires to study for Doctorate (one hour from Columbia) $3000.Apply with data on education, experience and references (includePastor) to: President Frederick Schweitzer. Bloomfield College,Bloomfield, -New Jersey. X

Engineers: E.E. and Chemical Engineers. For service in bay areasouth New Orleans. For persons seeking new experiencet in in-teresting area. Instrumentation, hydrographic data, occasional re-pair. Write Box B.F.E., College Station, Texas. X

Organic Chemists: Attractive positions in large expanding petro-leum research organization for Doctorate and Master's level organicchemists. All inquiries will be acknowledged. Box 418A,SCIENCE 8-27

Pharmacologist-.-M.S. or equivalent in Industrial Research. Willconsider Physiologist with pharmacological experience. Researchposition with Pacific Coast pharmaceutical firm. Salary openwith $3500 minimum. Box 434A, SCIENCE. 910

Physical Chemists or Physicists: For fundamental research onforces operating between small. particles, especially in clay-waterand soil systems. Should have knowledge of electrolyte theoryand surface phenomena. Three-year project with adequate fundsfor collaborators and assistants. Openings at both post-doctorateand pre-doctorate level with graduate study opportunity. WriteLloyd Wood, Chemistry Department, Cornell University, Ithaca,New York. 9-3

Personnel PlacementPOSITIONS OPEN

Positions Open: (a) Senior pharmacologist; research laboratories,biological manufacturing company; university medical center;East. (b) Associate professor in bacteriology; duties involve ac-tive teaching first five months, balance of time free for investiga-tion; East. (c) Biochemist; research program, large institutionlocated in university center; new research building: candidateswith advanced degrees and experience required; East. (d) In-,structor in anatomy; Ph.D. or young physician interested inanatomy as a profession; Pacific Coast. (e) Physician interestedin obstetrics-gynecology, with interest or training in vascular-renaldisease, or candidate with Master's or Ph.D., trained in vascular-renal physiology; will consider someone trained in the physiologyof climate and water balance; research appointment, department ofobstetrics-gynecology, university medical center. (f) Assistantprofessor in mental hygiene; position deals with problems of mentalhygiene and supervising school activities from point of view ofreventing maladjustments; university; South. (g) Chemists,B experienced in fields of organic, inorganic, physical or

analytical chemistry; preferably men experienced in industrial in-sulations, fiber products and resins; large industrial company;salary to $600 monthly. S8-3 Medical Bureau (Burneice Larson,Director), Palmolive Building, Chicago 11. X

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CHARGES FOR CLASSIFIED ADVERTISINGRegular settin l0¢ a word. Minimum charge $2.50 foreach insertion. A box number counts as 8 *ords of theadvertisement (e.g. 25 words plus box number equals 33words). Make checks payable to the AAAS. All inser-tions must be accompanied by correct remittance and sent14 days in advance of publication date to the AdvertisingDepartment, AAAS 15 Massachusetts Avenue. N. W..Washington 5, D. d5.

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SCIENCE, August 27, 1948., Vol. 108 15

THE IIICKETTSIAL DISEASES OF MAN

A NEW AAAS PUBLICATION

This new symposium volume, about to appear from the press, is a comprehensivesurvey of the general field of Rickettsial diseases in man. Among the 27 contributorsappear the names of many of the foremost American authorities on this important andrelatively new field of medicine.

The first group of papers includes discussions of the taxonomy, biology, isolation,and identification of vectors, and reservoirs of infection of the Rickettsial diseases of man.The second group of papers is devoted to discussions of serological reactions, the Weil-Felix reaction, the complement-fixation and agglutination reactions, and the preparationand standardization of Rickettsial vaccines. The final group of papers treats of insecti-cides, methods of their application, and mite controls.

Many of the contributors to this volume during World War II were on the battlefronts in Africa, Italy, France and Germany, protecting our troops and the local popula-tions wherever Rickettsial diseases prevailed. Rarely, if ever, have the authors of a medi-cal book had so wide and so successful practical experience in the very subjects on whichthey have written.

The Rickettsial Diseases of Man(7% x 10O, cloth bound)

Price per copy in cartons, postage prepaid, for orders accompanied by checks:

To AAAS members ...................... $5.25To thosewhoare not members ............................................................ $6.25

Address orders to AAAS Book Department, 1515 Massachusetts Ave., N.W.,Washington 5, D. C.

To: A.A.A.S. Publications1515 Massachusetts Avenue, N.W., Washington 5, D. C.

Please accept my order for the volumes checked above. My check in the amount of$ . is enclosed.

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16 SCIENCE,27, 1948, Vol. 108

SCIENCE, August 27, 1948, Vol. 10816

Another Deekmam development to simplify modern analyteial problems *..

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A few of the many BECKMANFlame Photometer Advantages* SIMPLE OPERATION: Samples are atomized and intro-duced at a uniform rote into a very hot oxygen and gas flamethrough a specially designed burner. The spectral emission linesof the elements are excited and the Spectrophotometer isolatesthese lines and measures their intensities relative to a blank or

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