div class=ts-pagebutton class=gotoPage data-page=1Page 1button div class=ts-imageimg data-url=dr-a-l-clarkhtmlpage=1 data-page=1 class=ts-thumb lazyload alt=Page 1: Dr A L Clark loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAIAAAACCAQAAADYv8WvAAAAD0lEQVR42mP8X8AwAgiABKBAv+vAXklAAAAAElFTkSuQmCC data-src=https:reader036vdocumentsinreader036viewer2022081823575068071a28ab0f07ae452ahtml5thumbnails1jpg width=140 height=200 divp© Nature Publishing Group1956pdiv