THE SCIENTIFIC AMERICAN BOOK OF PROJECTS FOR NEW YORK I960 SIMON AND SCHUSTER -%^ l m E AMATEUR SCIENTIST Experiments and constructions, challenges and diversions in the fields of Astronomy, Archaeol- ogy, Biology, Natural Sciences, Earth Sciences, Mathematical Machines, Aerodynamics, Optics, Heat and Electronics. Selected from Mr. Stong's clearing house of amateur activities, appearing monthly in SCIENTIFIC AMERICAN, and ex- panded with additional information, instruc- tions, notes, bibliographies — and postscripts, from readers. BY C. L. STONG INTRODUCTION BY VANNEVAR BUSH ILLUSTRATED BY ROGER HAYWARD ALL RIGHTS RESERVED INCLUDING THE RIGHT OF REPRODUCTION IN WHOLE OR IN PART IN ANY FORM COPYRIGHT © I960 BY C. L. STONG PUBLISHED BY SIMON AND SCHUSTER, INC. ROCKEFELLER CENTER, 630 FIFTH AVENUE NEW YORK 20, N. Y. FIRST PRINTING Material previously published in SCIENTIFIC AMERICAN is copyright © 1952, 1953, 1954, 1955, 1956, 1957, 1958, 1959, 1960 by Scientific American, Inc. LIBRARY OF CONGRESS CATALOG CARD NUMBER: 6044286 MANUFACTURED IN THE UNITED STATES OF AMERICA PRINTED BY THE MURRAY PRINTING COMPANY, FORGE VILLAGE, MASS. BOUND BY H. WOLFF, NEW YORK TO MIL CONTENTS INTRODUCTION BY VANNEVAR BUSH XVII ". . . the motivation of the scientist, profes- sional or amateur, is the sheer joy of knowing." PREFACE BY C. L. STONG XXI ". . . the fact that an experiment delivers an unexpected answer means simply that you have not asked the question you assume you have asked" I. ASTRONOMY 1. ASTRONOMICAL DIVERSIONS 3 A note about the delights of stargazing and some fascinating instruments devised to over- come the limitations of the human eye. 2. A SIMPLE TELESCOPE FOR BEGINNERS 5 For about $25 the amateur can construct a telescope more powerful than Galileo's. 3. A TRANSISTORIZED DRIVE FOR TELESCOPES 18 Telescopes must be turned slowly to follow the stars across the sky. Here is a way of turning one automatically by means of a mo- tor deriving its power from transistors. A. AN ELECTRONIC STAR-TWINKLE SUPPRESSOR 26 How to build an apparatus for making ex- ceptionally clear photographs of the planets. VII 5. AN ASTROPHYSICAL LABORATORY IN YOUR 38 BACK YARD With the addition of a spectrograph the tele- scope becomes a tool of immense power for probing, the mysteries of the universe. 6. USING SHADOWED STARLIGHT AS A YARDSTICK 53 How to use -fleeting star shadows cast by the moon for locating with great precision geo- graphical points on earth, 7 A UNIVERSAL SUNDIAL 62 By mounting a globe of the earth this way you can convert it into a universal sundial that yields a wealth of information about the earth's relative motion in the solar system. It gives you the hour of the day in distant lands, 8. A SUNDIAL THAT KEEPS CLOCK TIME 73 Some attractions of the sundial frequently overlooked by laymen. Instructions for con- structing a sundial which can be adjusted to keep clock time (including daylight sav- ing) anywhere in the Northern Hemisphere. 9. THE MOON IN "3-D" 80 With the aid of a mirror, and your own nose as a measuring rod, the photographs in this chapter will give you a "3-D" view of the moon. Notes on how the pictures were taken. II. ARCHAEOLOGY 1. SHOULD THE AMATEUR DIG? 85 The amateur's role in archaeology. How the hobby of surveying ancient ruins and arti- CONTENTS facts can give pleasure to the amateur and help his professional colleagues. 2. THE EXCAVATION OF WAPANUCKET NO. 6 90 How a group of amateurs with professional guidance unearthed an ancient Indian vil- lage and thereby upset some well-established conclusions about Indian culture. Important do's and donts for the beginner. III. BIOLOGY 1. HOW TO CULTIVATE HARMLESS BACTERIA 105 Adventures in gardening at the microscopic level. How to experiment with weed-killers popularly known as wonder drugs. 2. GROWING ALGAE ON A WINDOW SHELF 117 Even if you live in the city you can grow a pioneer crop of the minute plants which may some day become an important source of mans food. 3. HOW TO TRANQUILIZE A RAT 123 An experiment designed by a Michigan high- school girl. 4. HOW TO MEASURE THE METABOLISM 135 OF ANIMALS An Ohio high-school girl devised this appa- ratus. She describes its assembly and opera- tion and gives details of a typical experiment utilizing mice as subjects. 5. CHROMATOGRAPHY 142 An analytic technique, one of the most powerful known to biochemists, is used to separate chlorophyll from spinach leaves. IX 6. ZONE ELECTROPHORESIS 152 When a solution of chemical compounds is applied to an electrified sheet of porous pa- per an extraordinary phenomenon occurs which the amateur can use for analyzing subtle chemical mixtures. IV. THE NATURAL SCIENCES 1. "NATURES UNIMPORTANT PUZZLES" 167 A note about a great amateur naturalist, the late Walker Van Riper. 2. THE DELIGHTS OF HUMMINGBIRD STUDY 168 Walker Van Riper devised brilliant tech- niques for attracting and studying humming- birds. Here are some of his methods described in his own words. 3. RAISING MOTHS AND BUTTERFLIES AS 184 EXPERIMENTAL ANIMALS An amateur lepidopterist explains how he raises unusual species and prepares them for scientific study. 4. BIRD-BANDING FOR THE AMATEUR 194 How the amateur who becomes a licensed bird-bander can make valuable contributions to science in his own back yard. 5. HOW TO LIVE WITH REPTILES AND 202 AMPHIBIANS Follow these simple direction for raising rep- tiles at home and you can see a snake shed its skin, or witness the courting rites (at once comical and enthralling) of small desert liz- ards, or watch a dime-store turtle grow to a length of eight or ten inches. x CONTENTS V. THE EARTH SCIENCES 1. HOW TO KNOW THE ROCKS 217 To the amateur who learns to "read" in rocks the history of the earth's ever-chang- ing surface, mineral collecting becomes a doubly rewarding avocation. How to begin. 2. THE ATTRACTIONS OF AMATEUR SEISMOLOGY 228 How to locate distant earthquakes by the vibrations that shake your own back yard. Typical seismographs. An eminent seismolo- gist shows how amateurs can help the pro- fessionals. 3. AN ELECTRONIC SEISMOGRAPH 236 From a war-surplus magnet, some scrap metal, and a few electronic parts, you can build a sensitive instrument for detecting earthquakes and the approach of violent storms. 4. AN AMATEURS SEISMOLOGICAL 245 OBSERVATORY The design and construction of the instru- ments. How a well was turned into an earth- quake detector. 5. HOW TO TRACK EARTH SATELLITES 263 Basic equipment for Method 1: a piano and a radio set capable of picking up signals from an artificial satellite. Method 2 employs a set of sticks and a stop watch. 6. EXPERIMENTING WITH THE EARTHS CHARGE 272 Normally the air around your head is some 200 volts positive with respect to the ground underfoot, but what happens in a thunder- XI [...]... molecules from those of low energy 5 A HOMEMADE INTERFEROMETER 521 An experiment with the optical effect that imparts color to soap bubbles and blueness to the bluebird 6 A PIEZOELECTRIC CLOCK 532 The accuracy of electric clocks depends on the care with which the operator at the power station maintains constant frequency on the mains How to use the piezoelectric effect to make an electric clock keep accurate... the course of building a telescope are as fascinating as those which the instrument helps to explore Four of the nine projects and problems which comprise this section discuss the construction and use of such instruments For amateurs who enjoy a dash of variety in 4 A SIMPLE TELESCOPE FOR BEGINNERS their experiments, these projects invite excursions across the boundaries of many scientific disciplines... tool Hence the center of the mirror and edge of the tool grind fastest, the mirror becoming concave and the tool convex As grinding proceeds, the worker periodically turns the tool slightly in one direction and the mirror in the other In consequence the concavity assumes the approximate form of a sphere because mating spherical curves tend to remain everywhere in contact when moved over each other in... including optics, mechanics, electronics, chemistry and solid-state physics The concluding discussions take up instruments demonstrating the value of astronomy in everyday affairs All the projects are well within the compass of the average basement workshop and reach of the average pocketbook Those who would hitch their hobby to the stars can make no better start than to construct the small telescope... warming the tool, smearing it with a film of turpentine and warming the face of each square of pitch before placing it in contact with the glass The pitch facets should be beveled, which can be accomplished in part by cutting the edges of the wooden divider-strips of the mold at an angle This also 12 A SIMPLE TELESCOPE FOR BEGINNERS 2 Preparation of pitch facets for polishing lap facilitates the removal of. .. 377 It attacks the classic problem of the farmer, the fox, the goose and the corn — and signals when it's in trouble 2 A TICKTACKTOE MACHINE 384 The design of this simple machine closely resembles that of all electric calculating devices 3 SOME COMPUTER THEORY 386 Puzzle machines are not merely entertaining gadgets They offer insight into mathematical problems — and the working of digital computers... that each was perfect That such mirrors work satisfactorily is a tribute to the marvelous accommodation of the eye and to lack of discrimination on the part of the observer Beginners may nonetheless undertake the construction of a reflecting telescope with every expectation of success If the amateur has enough strength and mechanical ability to grind two 6 A SIMPLE TELESCOPE FOR BEGINNERS blocks of glass... every inch or so to a depth of one inch Center the cardboard on the ur ground side of the mirror, press the notched edges down along the side of the glass and secure them with several turns of adhesive tape The cardboard form now resembles the lid of a wide-mouthed jar Paint the facets with fresh rouge, add half a teaspoon of water to the center of the lap and, with the heat-insulating shield in place,... I R C U I T " PUZZLE CIRCUIT OR 388 An amateur describes three "pircuits" he constructed at the age of sixteen XIII CONTENTS 5 AN ELECTRONIC MOUSE THAT LEARNS FROM EXPERIENCE 394 With a few hand tools and junk parts, the amateur can build a robot that exercises choice and never makes the same mistake twice 6 COMPUTERS AND THE TERROR OF MATHEMATICS 398 A short sad note 7 THE PLEASURES OF MATHEMATICS... conform with the curve of the glass This process is called coldpressing At the end of the cold-pressing interval slide the mirror from the lap and bevel the edge facets to remove any bulges that have formed The mirror must now be fitted with a shield to insulate it from the heat of the worker's hands In the case of a six-inch mirror cut a disk of corrugated cardboard eight inches in diameter and notch its . THE SCIENTIFIC AMERICAN BOOK OF PROJECTS FOR NEW YORK I960 SIMON AND SCHUSTER -% ^ l m E AMATEUR SCIENTIST Experiments and constructions, challenges and diversions in the fields of. you can ac- curately measure the charge on a single electron. VII. MATHEMATICAL MACHINES 1. A PUZZLE-SOLVING MACHINE 377 It attacks the classic problem of the farmer, the fox, the goose and. accuracy of electric clocks depends on the care with which the operator at the power station maintains constant frequency on the mains. How to use the piezoelectric effect to make an electric