The largest medical library in the world, the National I.ibrary of Medi-

cine near Washington, D.C., contains over 3.1 million items of medical

infi~rmation in its collection. This international resource is an ideal

example of the intbrmation explosion that has overwhehned all of us in

the latter half of the twentieth century.

This book intends, in an entertaining way, to shrink this "informa-

tion overwhelm" and focus on today s human body as well as on the

high-tech medical technology that helps to keep it healthy. No claim of

completeness is made for obvious reasons. All medical specialties are

going through constant and rapid transformation. There is no way to

freeze this change, capture a topic thoroughly, and keep it completely

up-to-date.

Some 24,000 medical periodicals from around the world are sub-

scribed to by the National Library of Medicine each year; and tens of

thousands of new books and other printed matter are added to the

collection annually, bringing in about 18 million new pages of mate-

rial. This does not include the dozens of computer data bases that

provide easy access to some 5 million references, nor does it include

thousands of audiovisual resources.

The total holdings of the National Library of Medicine amount to

more than 1 billion pages of medical information. If they were laid end

to end, these pages could encircle the planet earth at the equator about

7 times. No single human being, indeed no large prof;~ssional group of

scientists and doctors could possibly comprehend, retain, or fully uti-

lize this vast depository of information. Certainly no one book or

multivolume set of books can do more than scratch the surface. R. R.

Bowker s Medical Books and Serials in Print, 1984 lists some 70,000 books

and periodicals in its pages--just a heahhy selection of the total in-print

literature. If the amount of medical literature astounds us, it is nothing

compared to how the human body itself can boggle our minds. Just as

the quasar--that bewildering, superpowerful, billions-ol:light-years-

distant cosmic nbject--is at the edge of human comprehension, so too

is the human body with its microcosmic mysteries and its 100 trillion

cells.