A LIGHT IN NATURE

[Music] so [Music] so order your thinking the philosopher descartes insisted on it begin with the most simple objects so as to rise as if by steps the knowledge of the most complex and so 300 years later you searched the waters of a scottish loch for a specimen of nitella a simple plant you know already that nitilla has electrical properties akin to those of human nerves so you subject your specimen to experiment [Music] where will it lead from the evidence to reasoning from the facts to theories perhaps to laws yesterday this was called the experimental philosophy now we call it science at work here in bombay seeking to release energy from the infinitesimal nuclei of the atoms of a heavy metal palomar mountain lining up a 200-inch telescope [Music] to explore the birth and death of stars in a cambridge laboratory piecing together a picture of something no one has seen before a molecule of the protein [Music] myoglobin pursuing the chemistry of life through a radioactive isotope injected into a grub studying the dark world of the oceans sampling its waters examining its creatures reasoning from the facts checking the reasoning against new facts [Music] meet now a gathering of scientists men and women who reason from the facts many different disciplines stand in this room nuclear physics geology zoology biophysics pathology chemistry botany crystallography physiology different disciplines a common experimental philosophy to which most of those present have made some distinguished contribution they're assembled for a meeting of the royal society of london that very famous society founded in 1660 for a very simple end to improve the knowledge of natural things retrace the steps that led so far recall the ancient world with us for so long that bent its skills to superstition the image of the cosmos contrived by medieval europe placing the earth firmly at the center of the universe recall the sudden collaborative breakthrough the polish monk copernicus confounding astrology launching the earth in its true orbit around the sun the danish courtyard bringing precision to the study of the planet's motions revealing to kepler son of a woman tried for witchcraft that their courses were ellipses [Music] galileo describing the heavens through a strange instrument objectivity and a different humility summed up by isaac newton i seem to have been only like a boy playing by the seashore whilst the great ocean of truth lay all undiscovered before me ah here's a star now and what's that one what's in here uh proton primary yeah yes and um three four five six seven eight nine secondary sounds just about normal and how many mesons in this let's sink only one the same collaboration now a team in europe plots results obtained from this machine in berkeley california ready right clear all unshielded areas ready to accelerate beam a few years since rutherford smashed the atom now they smash particles of atoms and discover new ones basically this is a huge electromagnetic sling hurling protons against a target at almost the speed of light flinging the resulting particles into a tank of liquid hydrogen making the disintegrating fragments reveal their path and nature [Music] dissecting the stuff the world is made of [Music] seeking to pin down those strange subatomic forces glowing for a fraction of a moment vanishing that we don't yet understand [Music] francis bacon caught the spirit of this quest if a man could succeed not in striking out some particular invention but in kindling a light in nature in ringing a bell to call other wits together he would disclose all that is most hidden and secret in the world the royal society called the wits together and does so still to kindle in each other's company a light in nature to a few like-minded men a king granted their charter they and their kind wrote a new charter for the human race harvey pasteur lister issuing their challenge to distress the curious little toy designed by hiro set to bridge the turning earth [Applause] priestly shayla lavoie releasing the infinite potential of the elements galvani bursted faraday launching revolutions wider than all the schemes of statecraft yet these have been the offshoots of inquiry seldom its first concern first now as always comes the assault on undiscovered truth mr president ladies and gentlemen the results to be presented today represent an attempt to gain information concerning the general mechanism of cell growth and differentiation by making determinations on groups of successive segments cut from the tip of seedling p and bean roots towards the base this experimental approach depends upon the fact that roots possess a terminal meristem [Music] in these three centuries the scale of the assault has multiplied organized investigation breaks into the secret realms the experimental philosophers now are governments industries universities yet the cast of mind of early science governs science still [Music] expedition sounding the antarctic ice cap as part of the international geophysical year [Music] a lonely team preparing to sink in the bath escape six seven eight miles into the mariana trench all accept instinctively what newton taught first diligently inquire into the properties of things then proceed more slowly to hypotheses for the explanation of them the tools of course are more refined today huygens postulated the wave theory of light here they're using the different wavelengths of light of precisely defined colors to measure length to a millionth of an inch [Music] [Music] another new tool an atomic clock tuned to the radio waves absorbed by the atoms and a beam of cesium vapor it's accurate enough to reveal changes in the speed of the earth's rotation leon hook's microscope laid bare a world never seen before this instrument using electrons in place of light rays opens up another place a tiny flake of metal in the electron beam then increase the magnification and reveal the hidden flaws that worn a weakness contact between parallel moving minds new aids to inquiry these permit the ever deeper questioning of nature crystals of common substances how do they grow how is their strength related to the pattern of their growth could the strength of these tiny non-metallic crystals be preserved developed into materials stronger than steel if so in what conditions why are leaves green or rather what are the properties of this green pigment chlorophyll what are the hidden forces within it provoked by sunlight to cause the interaction of carbon dioxide and water what questions will yield definite replies which methods will coax them out and when you've translated your questions into numbers the alphabet of science how best to work them out how to set up your program so that the computers can sort and sift and analyze [Laughter] and sometimes nature gives you only enigmatic answers to be pondered wrestled with debated answers confronting us as one physicist has put it with a vast jumble of new numbers an insulting lack of obvious meaning then in one sense it stays the same namely its total volume is not altered in another sense it's all it's different so uh are you going to say it's the same or different you can say either way depending on which property you want to think about but i think it has got a point in this the following up to now we have said that the system is going to be in its lowest energy state because if we discuss from the probabilistic point of view we see that if we have a background this is the most the highest point i mean you cannot discuss the thing without reference to development in time really or if it is no but in what way will it be stable you see you have no way to say this because you don't know what is to what is order it's always changing in time it's always different [Music] three centuries of measuring questioning pattern seeking and gatherings of scientists the world over like this great congress in the soviet union pursue the ends that mark the royal society's first meeting in 1660 to exchange results look ahead plan the lines of fresh enquiry where do the frontiers stand today in what fields are the most significant advances likely in the coming years one such field affects us all it's the investigation of the living cell the effort to explain life in terms of chemistry [Applause] [Music] what makes us as we are what makes us alike as a species different as individuals the geneticist attacks this problem why we are alike and why we are different by studying fruit flies he's been studying them for fifty years they breed fast in a year or so he can examine the equivalent of seven hundred years in man he sees that peculiarities appear making the flies different from each other variations in the color of the eyes for example why in every tiny cell of the fly's body are strings of chromosomes carriers of hereditary instructions and each peculiarity is due to some change in one of these strings an irregularity here and a bar eye results life maintains itself by cell division thousands of cells in your own body are dividing like this now and the chromosomes of the parent cell divide also passing to each daughter cell an exact copy of the hereditary instructions but how the chemist takes a mass of living cells from a freshly killed rat he separates out in the centrifuge the material within the chromosomes that carries the hereditary instructions [Music] this is it the stuff that somehow governs what we are [Applause] what's it made of fundamental chemical research revealed phosphate groups and four compounds nucleosides made up of bases combined with a rare sugar deoxyribose so they called the substance this stuff that determines life deoxyribonucleic acid dna the chemist sees it as a chain of different groups of atoms but under the most powerful electron microscope the molecule is seen only as a mere thread how can we get closer find out how the chains of atoms are arranged along the thread-like molecule they puzzled out a chemical sketch sugar and phosphate atoms along the backbone the four compounds forming side links [Music] but a hypothesis on paper is one thing what does it look like in reality here the physicist can help he draws the dna into a fiber as it lengthens so the thread-like molecules align themselves in a regular pattern that allows him to use his most powerful tool x-ray crystallography his method is to make the fine atomic structure of the dna reveal its shape by scattering the even finer x-rays he plays the x-ray beam on the dna for four to six weeks makes it break up the beam to reveal on a photographic plate an image which he can mathematically relate to the atomic structure of the molecule and so by intricate calculation and a brilliant guess we get a model of something no one has ever seen of the giant molecule of dna and we find in this enormous complexity not one chain of atoms but two two chains with up to thirty thousand atomic links coiled around each other suggesting a template mechanism of reproduction we know now that it's the different order of arrangement of the atoms along these chains that spells out the code dictating the character of life man or mouse you or me as the chains unwind as the chromosomes part as the cells divide to make a new living creature [Applause] why are we as we are the questions darwin and mendel first posed we are beginning to answer precisely one day who knows we may break the hereditary code itself would you just check that pgr electrode there's enough slack on the wires though just tug that a little bit would you change to a bit awkward investigating the most complex organic pattern known the 10 000 million nerve cells that make up the human brain how do we learn the zoologist studies the learning process by experimenting with an octopus this octopus is learning that if it goes for the crab when a white disc is showing it gets an electric shock it learns to recognize the disc as dangerous and hold back where does this learning come from remove a certain lobe of the brain and try again the lesson is forgotten in this lobe then lies the seat of memory are your legs quite comfortable yes thanks when this girl's mind learns to associate a light with an unpleasant noise she'll be able to stop the noise the minute electric currents set up as her brain learns will be picked up by electrodes on the surface of the skull and recorded [Applause] [Music] the brain at work grappling with a problem striving to learn first steps towards fuller comprehension of our memory experience consciousness another field of present concentration is the deeper exploration of the heavens [Music] [Applause] [Music] areas of crashing turmoil in the seeming calm of the sky [Music] picked up by the radio telescope at jodrell bank as it probes towards the limits of the universe scan 30 declination 31 degrees 25 minutes right ascension 20 hours 50 minutes intensity 28.1 hundreds upon hundreds of radio sources what are they exploded stars writhing gas clouds galaxies that collided before the dinosaurs evolved slowly the blanks in the map of space are beginning to be filled and now the technologist is arming the science of the heavens with a new tool of exploration the instrument carrying satellite the electronic telescope located in space itself [Music] [Applause] [Music] uh oh [Applause] [Music] [Applause] [Music] so [Music] 300 years of labor intuition [Music] and what has now been found and proved and built on only reveals how great is still the ocean of undiscovered truth how urgent still to kindle a light in nature to disclose all that remains hidden and secret in the universe [Music] [Applause] [Music] so [Music] [Applause] [Music] [Applause] [Music] [Applause] [Music] you