Historical Glimpses

The X Factor Editor's Note:

Apart from being an indispensable aid to thorough dental examination, radiographs are an essential part of endodontic treatment. The following article by Robyn Williams provides some historical background of the discovery that changed the world. The article appeared in The Australian Way February I996 and is reprinted here with permission.

It is Adelaide, November 1995. A white-haired old man almost the age of the century stands to address a huge formal dinner at a city hotel. With his stick propped against the side of the lectern. he looks calmly through his spectacles at the audience and, with elegant. even powerful sentences, speaks of the importance of scientific research.

He talks of the unexpected bonanzas that can be xovided by discoveries like that of the X-ray by Wilhelm Roentgerl. Roentgen, he explains. refused to patent his discovery, saying it was for the benefit of all humanity. And the Nobel Prize money, ;;wen him in 1901 and the first-ever awarded for physics. was p-esented by Roentgen to his university at Wurzberg "Money . . . economics isn't everything. you see!" the speaker rays. pausirg. blinking at the lights. before adding: "Thank you for being so kind to a silly old man."

Sir Mark Oliphant, 94, receives a standing ovation ,as he slowly resumes his seat. He was born six years after Wilheltn Roentgen discovered X-rays. He was educated at Adelaide University's Department of Physics, where some of the first X-ray experiments were performed in Australia, and he knew the two B-aggs. father

and scn. whose ideas would open up a whole new field of X-ray crystallogra- phy.

It was Oliphant who would later travel to Cambridge and become the right-hand man. al- most a son. to Lord Rutherfo-d, the gen- ius who split the atom. Aqd when it was shown. later, how a chain reaction could release stu- pendous amounts of energy from the nucleus. it was Oli- phant who carried the letter revealing this astomding sec- ret to the United States, to Ernest Lawrence, who con- veyed it 10 President

Ground breaker. German physicist Wilhelm Roentgen

Theodore Roosevelt The result was the Manhattan Project (the code name for the successful attempt during World War II to produce an atomic bomb in Amenca) After the invention of "The Bomb at Los Alamos. Oliphant returned to Cambridge. then to Canberra In I97 I he became Governor of South Australia Who better then to celebrate the Roentgen discovery and its first application here in 1896'

But back to the beginning It was Friday evening. November 8 1895, in the university town of Wurzberg, Bavaria The professor of physics. a handsome but somewhat severe figure. was experi- menting with an induction coil and a glass tube. partially cleared of air and connected with electrodes When he switched on the apparatus he saw something more than the common cathode ray fluorescence that had been known for 20 years Roentgen saw that a chemically-treated paper beyond the apparatus had begun to glow Rays of some sort were reaching across the lab Roentgen put a thick book in their way The paper still glowed'

So it was that the world changed Physics leapt forward A stunning new tool became available to medicine A way of investigating molecules was soon invented - molecular biology became a brand new field of science A means for detecting art forgeries and for examining mummies or fossils without destroying them was at hand And now. today, beyond the dreams of Roentgen, we have scanners that can look into the body and take pictures in virtual slices to see how it works and whether there may be tumours or lesions in delicate tissues such as the brain

A hundred years ago they feared that X-rays would reveal more than that. This is part of an account written by H J W Dam of McClure's Magazine. New York. who visited Roentgen in early 1896.

'Now then," he said smiling and wrth some impatience. when some personal questions at which he chafed were over. "'you have come to see the invisible rays?" "Is the invisible. visible?" "Not to the eye, but i t s results are Come in here Step inside, said he opening a door which was on the side of a box farthest from the tube I immediately did so. not altogether certain whether my skeleton was to be photographed for general inspection or my secret thoughts held up to the light on a glass place. "

Not only did they fear that X-rays would reveal thoughts. They also feared that their nakedness would be exposed under their apparel, so X-ray proof corsetry was soon touted by hucksters to take advantage of the panic.

X-rays came to Australia remarkably soon after their discovery. The Professor of Physics at Adelaide, William Henry Brag. managed to transcend the agonisingly slow communications of the time (the occasional ship) by getting news of the X-ray via the new Overland Telegraph which linked wfih a cable line in Palmemon. Western Australia, to Java, Indonesia. and out to the world. An article on X-rays, published in London's Nature magazine on January 26. 1896, described details of the process and Brag took it from there.

Brag's son. Lawrence, then famously broke his elbow. I always thought it was from falling off his bike. others say he fell from a tree.

AUSTFWAN ENDODONTIC :OURNAL VOI UME 2s NO 2 AUGUS~ 1998 PAGE 91

"I well remember my father's first experiments wrth X-ray tubes . . . I think I must hove been among the first to be employed as a patient . . . The flickering greenish light. crackling and the smell of ozone were sficiently terrifiing to impress the incident clearly in a child's mind. "

Lawrence Bragg was five. Ten years later he graduated from St Peter's. Adelaide. to read mathematics at the university. At the age of only 22 he was able to correct his father's erroneous theories about the nature of X-rays. W. H. had imagined that there were pores in matter, like holes in a cheese. through which the rays travelled. Lawrence, instead. described radiation of very short wavelength passing through the virtual empty space of atomic structures.

could not attend. Professor Bragg has promised to repeat the lecture. probably in the Town Hall. "

Fifty years later, Lawrence Bragg and the team he led at Cambridge. using X-ray methods to reveal the shape of complex molecules, collected nine Nobel Prizes between them, including those of Watson and Crick, for the structure of DNA. That was at the Cavendish Laboratory in Cambridge where Sir Mark Oliphant was a member of another famous team.

Today there are about 5000 radiographers in Australia. Their work has moved light-years beyond the startling effects of those green crackling tubes. They save many lives each year and perform daily miracles. Rarely has so much come from one discovery pinpointed to one evening long ago and taken up with such enterprise so far away.

Robyn WllliiS

The Australian Way

X-ray pioneer: Nobel Rize-winner Australian Wlliom Henry Bragg.

At the age of 25. he, with his father, shared the Nobel Prize for physics. Sir Lawrence Bragg is the youngest person ever to be made a Nobel Laureate and the only one, as far as I know, to be able to celebrate the 50th anniversary of receiving the award.

But X-rays had been used in Australia even before young Lawrence had his elbow examined. On March 4 1896 Professor Thomas Lyle confirmed Roentgen's discovery. On May I6 1896, The Australian newspaper reproduced a radiograph of a rat taken by a Mr Selby of Malvem. Victoria. On May 30. 1896. the South Australian Register records Mr Barbour and William Bragg producing a radiograph of a hand. In June, The Australian reports an X-ray of a flounder. Then the Bathurst Free Ress trumpets a successful operation on the hand of one Eric Thompson following a radqraph made on July 25 by Father J. F! Slattery in the science hall at St Stanislaus College.

Father Slattery is acknowledged as the first Australian to use X- rays for diagnosis; he was one of seven people featured in a series of postage stamps issued by Australia Post to commemorate the centenary.

It is hard to overstate the sensation caused by the new physics. This is an account given by the South Australian Register on June 18, 1896.

A conviction has been obtained in the District Court, Melbourne, by the Veterinary Board of Victoria, agrunst H.W. Hoaglund, for having exposed a sign bearing the words "Veterinary Dentist".

hwnlheAuscrrlianJournrldDentistry 1898;257

"The great interest monrfested in the wonderful discovery of the Roentgen rays rn attested by the large audience at the Unrveruty Lbrory on Wednesday evening, when Rofessor Brag lectured on the subject. The opprrcotion for seots was for in excess of the accommodatm in the spocious holl, and a crowd of people hod to go may disoppornted at being unable to goin odmission. Howevec for the benefit of those and others who

PAGE 92 AUSTRALIAN ENDOOONTIC JOURNAL VOLUME 24 No. 2 AUGUST 1598