18 REPORT—1885. 
important manufactures arose from an increased knowledge of facts, 
around which scientific conceptions were slowly concreting. Aristotle 
defines this as science when he says, ‘Art begins when, from a great 
number of experiences, one general conception is formed which will 
embrace all similar cases.’ Such conceptions are formed only when 
culture develops the human mind and compels it to give a rational 
account of the world in which man lives, and of the objects in and around 
it, as wellas of the phenomena which govern their action and evolution. 
Though the accumulation of facts is indispensable to the growth of science, 
a thousand facts are of less value to human progress than is a single one 
when it is scientifically comprehended, for it then becomes generalised in all 
similar cases. Isolated facts may be viewed as the dust of science. The dust 
which floats in the atmosphere is to the common observer mere incoherent 
matter in a wrong place, while to the man of science it is all-important 
when the rays of heat and light act upon its floating particles. It is by 
them that clouds and rains are influenced ; it is by their selective influence 
on the solar waves that the blue of the heavens and the beauteous colours 
of the sky glorify all Nature. So, also, ascertained though isolated facts, 
forming the dust of science, become the reflecting media of the light of 
knowledge, and cause all Nature to assume a new aspect. It is with the 
light of knowledge that we are enabled to question Nature through direct 
experiment. The hypothesis or theory which induces us to put the ex- 
perimental question may be right or wrong; still, prudens questio dimidium 
scientice est—it is half way to knowledge when you know what you have 
to inquire. Davy described hypothesis as the mere scaffolding of science, 
useful to build up true knowledge, but capable of being put up or taken 
down at pleasure. Undoubtedly a theory is only temporary, and the 
reason is, as Bacon has said, that the man of science ‘ loveth truth more 
than his theory.’ The changing theories which the world despises are 
the leaves of the tree of science drawing nutriment to the parent stems, 
and enabling it to put forth new branches and to produce fruit ; and 
though the leaves fall and decay, the very products of decay nourish the 
roots of the tree and reappear in the new leaves or theories which succeed. 
When the questioning of Nature by intelligent experiment has raised 
a system of science, then those men who desire to apply it to industrial 
inventions proceed by the same methods to make rapid progress in the 
arts. They also must have means to compel Nature to reveal her secrets. 
A@neas succeeded in his great enterprise by plucking a golden branch 
from the tree of science. Armed with this even dread Charon dared not 
refuse a passage across the Styx ; and the gate of the Elysian fields was 
unbarred when he hung the branch on its portal. ‘l'hen new aspects of 
Nature were revealed— 
Another sun and stars they know 
That shine like ours, but shine below. 
It is by carrying such a golden branch from the tree of science that in- 
