From Falstaff to the Ring of the Nibelungen, great constructions and great works of art have paid a price for amplitude beyond usual standards. D'Arcy Wentworth Thompson (1860–1948), Professor of Zoology at Scotland's University of St. Andrews, and perhaps the greatest polymath of our century, was scarcely homo unius libri (a man of one book). He composed two volumes of commentaries on all birds and fishes mentioned in classic Greek texts; he prepared the standard translation of Aristotle's Historia animalium; he labored for years over statistics for the Fishery Board of Scotland; and he wrote the section on pycnogonids (a small but fascinating group of arthropods) for the Cambridge Natural History series. But his enduring (indeed evergrowing) fame rests upon a glorious (and very long) book that served more as the active project of a lifetime than a stage of ontogeny—On Growth and Form (first edition of 793 pages in 1917, second edition enlarged to 1116 pages in 1942).

Much as it must pain any scholar and publisher of integrity to abridge such a work (for such an act does resemble the dissection of a body), one must not, as Jesus told us, light a candle and then place it invisibly under a bushel (Matthew 5:14–17). On Growth and Form is one of the great lights of science (and of English prose); it must be available at an affordable price and a totable heft: “Let your light so shine before men, that they may see your good works.”

‘Science seems to be either all good or all bad. For some, science is a crusading knight beset by simple-minded mystics while more sinister figures wait to found a new fascism on the victory of ignorance. For others it is science which is the enemy; our gentle planet, our slowly and painfully nurtured sense of right and wrong, our feel for the poetic and the beautiful, are assailed by a technological bureaucracy – the antithesis of culture – controlled by capitalists with no concern but profit. For some, science gives us agricultural self-sufficiency, cures for the crippled, a global network of friends and acquaintances; for others it gives us weapons of war, a school teacher's fiery death as the space shuttle falls from grace, and the silent, deceiving, bone-poisoning, Chernobyl.

Both of these ideas of science are wrong and dangerous. The personality of science is neither that of a chivalrous knight nor pitiless juggernaut. What, then, is science? Science is a golem.

A golem is a creature of Jewish mythology. It is a humanoid made by man from clay and water, with incantations and spells. It is powerful. It grows a little more powerful every day. It will follow orders, do your work, and protect you from the ever threatening enemy. But it is clumsy and dangerous. Without control a golem may destroy its masters with its flailing vigour; it is a lumbering fool who knows neither his own strength nor the extent of his clumsiness and ignorance.

A golem, in the way we intend it, is not an evil creature but it is a little daft. Golem Science is not to be blamed for its mistakes; they are our mistakes. A golem cannot be blamed if it is doing its best. But we must not expect too much. A golem, powerful though it is, is the creature of our art and our craft.’

With the exception of most of Chapter 1 and the whole of Chapter 3, the substantive parts of this book are largely expositions of others’work; in this we follow the pattern of the first volume in the Golem series.Thefull bibliographic references to the works discussed both in this Preface and the other chapters, as well as additional reading, will be found in the Bibliography at the end of the volume.

As for the substantive chapters, Chapter 1 is Collins’s redescription of the argument over the success of the Patriot missile. It is heavily based on the record of a Congressional hearing that took place in April 1992, and on two papers written by principal disputants, Theodore Postol and Robert Stein; it also draws on wider reading. Though this chapter is not a direct exposition of anyone else’s argument, and though it uses a new analytic frame-work turning on different definitions of success, it must be made clear that the account was made possible only because of Postol’s prior work. Also, Postol was extremely generous in supplying Collins with much of the relevant material and drawing his attention to more. Collins has tried to make sure that the account is not unduly influenced by Postol’s views and that the material on which it draws represents the field in a fairway. Itwill be noted that the chapter does not repeat Postol’s expressed position – that no Scud warheads, or almost no Scud warheads, were destroyed by Patriot missiles – but stresses the difficulty of reaching any firm conclusion while keeping open the strong possibility that Postol is right.

These words were uttered in 1984 by the late Sir Walter Marshall, chairman of Britain's then Central Electricity Generating Board (CEGB). The CEBG used the rail system to transport spent nuclear waste from its generating plants to its reprocessing plants. In spite of the fact that the fuel was contained in strong containers, or flasks, the public was not happy. The CEGB therefore arranged for a diesel train, travelling at a hundred miles per hour, to crash head-on into one of their flasks to show its integrity. Sir Walter's words were spoken to the cameras immediately following the spectacular crash, witnessed by millions of viewers either on live television or on the nation's televized news bulletins. Sir Walter was claiming that the test had shown that nuclear fuel flasks were safe. (The source from which Sir Walter's quotation was taken and of the basic details of the train crash is a video film produced by the CEGB Department of Information and Public Affairs entitled ‘Operation Smash Hit’.)

Surface-tension

We pass from the solitary cell to cells in contact with one another—to what we may call in the first instance ‘cell-aggregates’, through which we shall be led ultimately to the study of complex tissues. In this part of our subject, as in the preceding chapters, we shall have to consider the effect of various forces; but, as in the case of the solitary cell, we shall probably find, and we may at least begin by assuming, that the agency of surface-tension is especially manifest and important. The effect of this surface-tension will manifest itself in surfaces minimae areae: where, as Plateau was always careful to point out, we must understand by this expression not an absolute but a relative minimum, an area, that is to say, which approximates to an absolute minimum as nearly as the circumstances and material exigencies of the case permit.

Let us restate as follows, in terms of Energy, the general principle which underlies the theory of surface-tension or capillarity.

When a fluid is in contact with another fluid, or with a solid or with a gas, a portion of the total energy of the system (that, namely, which we call surface-energy) is proportional to the area of the surface of contact; it is also proportional to a coefficient which is specific for each particular pair of substances and is constant for these, save only in so far as it may be modified by changes of temperature or of electrical charge.

The accident at the Chernobyl nuclear power plant in the Soviet Union on 26 April 1986 is one of the defining moments of the nuclear age. It is the worst nuclear accident ever: a melt-down of the core of a reactor, followed by an explosion and fire releasing tons of radio-active debris into the atmosphere. The accident not only killed nuclear workers and firemen who fought to save the doomed reactor, but also condemned many others who lived under the path of the fallout to illness and premature death or a life of waiting for a hidden enemy. The weather, no respecter of nation states, carried its deadly passenger far and wide.

Of the chemistry of his day and generation, Kant declared that it was a science, but not Science—eine Wissenschaft, aber nicht Wissenschaft—for that the criterion of true science lay in its relation to mathematics. This was an old story: for Roger Bacon had called mathematics porta et clavis scientiarum, and Leonardo da Vinci had said much the same. Once again, a hundred years after Kant, Du Bois Reymond, profound student of the many sciences on which physiology is based, recalled the old saying, and declared that chemistry would only reach the rank of science, in the high and strict sense, when it should be found possible to explain chemical reactions in the light of their causal relations to the velocities, tensions and conditions of equilibrium of the constituent molecules; that, in short, the chemistry of the future must deal with molecular mechanics by the methods and in the strict language of mathematics, as the astronomy of Newton and Laplace dealt with the stars in their courses. We know how great a step was made towards this distant goal as Kant defined it, when van't Hoff laid the firm foundations of a mathematical chemistry, and earned his proud epitaph—Physicam chemiae adiunxit.

We need not wait for the full realisation of Kant's desire, to apply to the natural sciences the principle which he laid down. Though chemistry fall short of its ultimate goal in mathematical mechanics, nevertheless physiology is vastly strengthened and enlarged by making use of the chemistry, and of the physics, of the age.

In this chapter and the following ones D'Arcy Thompson is straggling against the notion that all form can simply be explained by heredity, and that therefore changes in form inevitably map out phylogenetic relations. Instead he repeatedly suggests that physical forces (such as those which produce the variations of shapes of snow-flakes) are of prime importance and relationships of shape may not justify any family tree or a sequence in time, but simply show mathematical kinship. Today we are inclined to combine the two and say that the genes, the units of heredity, do control shapes, but that the activities of genes are constrained by the physico-chemical properties of the chemical substances and the configuration of these substances present in the organism. This does not touch upon the question of whether or not all the shapes produced are adaptively significant. D'Arcy Thompson's strong arguments that they are not is a reaction against those who see a selective advantage to all structures. But this issue cannot be resolved without an ecological study of each example, a Gargantuan task that is unlikely ever to be achieved. All we can say at the moment is that there is no a priori reason why some structures, which have been initiated by mutation and formed within the confines of physico-chemical laws, should not utterly lack any adaptive significance, and yet remain fixed in the population. It might even be argued that a particular gene-change produced other effects that were adaptively significant and these less obvious gene-effects elicited the selection pressure which preserved the adaptively inert structure in the population.

Every schoolchild sooner or later learns the standard story of the origins of oil; it runs something like this. Once upon a time, hundreds of millions of years ago, the earth was covered by vast oceans. Animals, plants and micro-organisms in the seas lived and died by the billion, their remains sinking to the bottom and mixing with sand and mud to form marine sediment. As the ages passed, the mud turned to rock and eventually the organic mass became buried deep under layers of rock. The oceans receded and the earth's crust heaved and buckled. Compressed under this vast weight of rock, decomposition occurred and the layers of biomass underwent a chemical change to form hydrocarbons (compounds composed only of hydrogen and carbon atoms) – coal, oil, and natural gas.

Special geological conditions are needed to keep the oil trapped underground. The organic material has to be covered by porous rocks and these, in turn, have to be covered by an impermeable layer which acts as a cap to prevent the oil and gas escaping. Oil is consequently found only in places where these geological conditions are met.

This is the most celebrated chapter of the book and it has been widely commented upon in biological literature. I have not made any careful survey, but I suspect that the well-known diagrams of transformations have been reproduced in sundry scientific writings a large number of times.

The comments almost invariably have a few points in common, which I shall briefly summarise here. In the first place it is surprising that despite their fame, the Cartesian transformations have been used very little. This is because, to use Medawar's term, they are ‘analytically unwieldy’. The few times the method has been applied is in the development or change of form in a single system, as for instance, Richards and Riley's study of developing amphibians under different conditions, and Medawar's analysis of tissue culture growth.

A far more significant result in terms of practical application is that the system of transformations of D'Arcy Thompson stimulated and contributed to the much simpler method of analysis of allometric growth, which has found widespread use, mainly through the work of J. S. Huxley. Here instead of attempting to analyse a whole structure in two (or three) divisions, two factors are isolated and compared on a logarithmic scale. In this way it is possible to discover the ratio of the growth-rates of different structures, a method which has found application in embryology, taxonomy, palaeontology and even ecology.

Famille des polygalées