The science of life : fully illustrated in tone and line and including many diagrams

Man has always been, and still is, disposed, perhaps instinctively, to suppression and panic at plain statement; it is the hardest task of the educationist to train him to look facts in the face. He is curious by natureyes, but he is meanly and furtively curious. He does not like to be caught looking or suspected of thinking. About the body a cleanly frankness is the last achievement of our civilization. There are millions of people in the world who have never contemplated themselves unclothed in a mirror, and would not willingly do so. Many religious orders deny their votaries an entire bath. There is a real natural and instinctive resistance to biological knowledge in the mass of mankind, and the nearer that knowledge approaches to our own minds and bodies, the intenser the resistance becomes.

The resistances to knowledge are not merely passive. It is not only that most human beings are indisposed to know and learn ; they are afraid of and hostile to all that they do not know and they seek to prevent it in others. The human mind is much more tortuous and indirect than it will consciously admit; it often fails to understand its own motives. Since the great revival of scientific work in the sixteenth century there has been a steady undercurrent of deprecation and antagonism which rises very easily to active obstruction and suppression. ‘The self-love of the ignorant has demanded that the man of science, in play and story, should be caricatured, ridiculed, and misrepresented. From Laputa to the Pickwick Club, British literature, for example, spits and jeers at its greater sister, and to devote a life to science and the service of truth is still to renounce most of the common glories and satisfactions of life for a hard and exalted mistress. But while the pomps and glories of every other sort of human activity fade and pass, the growth of science is a continuing and immortal thing.

_The revival of biological enquiry and free biological teaching became remarkable in the sixteenth century. An increasing number of active minds directed themselves to observing, collecting, and classifying. Art was becoming observant and more sedulously representative. Dissection at first was quite as much artistic as medical and surgical in its aims. ‘There is a strong decorative purpose apparent in many early science collections. They consisted of “ curiosities,” not specimens. The student, turning over the notebooks of Leonardo da Vinci, finds there the artist and scientific man inex-

INTRODUCTION

tricably mingled. From the studio and the private investigations of dissatisfied medical men, far more than from the bookish study, did the modern science of life arise. Modern science owes more to art and natural curiosity and less to literature and philosophy than is commonly understood.

The geographical exploration of the fifteenth and sixteenth centuries was an enormous stimulant of biological work. The invigorating influence of practical benefit was supplied by the acclimatization of new food plants, the application of new medicinal substances, the production and importation of such commodities as canesugar, tobacco, tea, coffee, and a great variety of economically valuable novelties.

The development of the microscope in the

Fig. 2. The microscope with which Robert Hooke (1635-1703) discovered vegetable cells.

The microscope itself is on the right ; on the left are a lamp

and a glass globe filled with water, for focusing a spot of

brilliant light on to the object under examination. (This

and Fig. 1 by courtesy of the Royal Microscopical Society of London).

seventeenth century meant a mighty enhancement of scientific observation. It revealed not only a whole new world of unsuspected life-forms, but a thousand structural secrets too fine for the scalpel. In many of its branches the advance of biology has been determined by the progress of microscopy. A third great mine of contributory knowledge was opened up by the study of fossils, of which Nicholas Steno (1638-1686) was the pioneer. ;

Biological science remained largely observational for three centuries, passing slowly from the development of botanical and zoological gardens and the industrious collection of shells, bones, fossils, flowers, fruits dried and preserved, specimens of all sorts, to dissection and the microscopic examination of tissues and living structure,