164 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
[August 31, 1872. 
his business in relation to the great life of mankind; 
that the noble army of practical workers may recog- 
nize. their fellowship with the outer world, and the 
spirit which must guide both; that this so-called outer 
world may see in the work of science only the putting 
in evidence of all that is excellent in its own work— 
may feel that the kingdom of science is within it. 
These are the objects of the present discourse, and you 
will see that they compel me to choose such portions of 
my vast subject as shall be intelligible to all, while they 
ought at least to command an interest universal, per¬ 
sonal and profound. In the first place, then, I want 
to explain what is meant by scientific thought. You 
may have heard some of it expressed in the various sec¬ 
tions this morning. You have probably also heard 
expressed in some places a great deal of unscientific 
thought, notwithstanding that it was about mechanical 
energy, or about hydrocarbons, or about eocene deposits, 
or about malacopterygii; for scientific thought does not 
mean thought about scientific subjects with long names. 
There are no scientific subjects. The subject of science 
is the human universe; that is to say, everything that 
is, or has been, or may be related to man. Let us, then, 
taking several topics in succession, endeavour to make 
out in what cases thought about them is scientific, and 
in what cases not. Ancient astronomers observed that 
the relative motions of the sun and moon recurred all 
over again in the same order about every nineteen 
years. They were thus enabled to predict the time at 
which eclipses would take place. A calculator at one of 
our observatories can do a great deal more than this. 
Like them, he makes use of past experience to predict 
the future; but he knows of a great number of other 
cycles besides that one of nineteen years, and takes ac¬ 
count of all. of them; and can tell about the solar 
eclipse of six years hence exactly where it will be 
visible, and how much of the sun’s surface will be co¬ 
vered at each place, and, to a second, at what time of 
day it will begin and finish there. This prediction in¬ 
volves technical skill ox the highest order; but it does 
not involve scientific thought, as any astronomer will tell 
you. By such calculations the places of the planet 
Uranus at different times of the year had been pre¬ 
dicted and set down. The predictions were not fulfilled. 
I .hen. arose Adams, and from these errors in the pre¬ 
diction he calculated the place of an entirely new 
planet, that had never yet been suspected; and you all 
know how the new planet was actually found in that 
h acc ‘ ^ ow this prediction does involve scientific 
thought, as any one who has studied it will tell you. 
Here there are two cases of thought about the same 
subject, both predicting events by the application of 
previous experience; yet we say that one is technical and 
the other scientijic. 
T^\wL’ ] et i US J ake sample from, the building of 
bridges and roofs. When an opening is spanned over 
! Ba construction, which must bear a certain 
^ e ht n r th0Ut enough to injure itself, there 
aie two forms m which this construction can be made ; 
and u 5 h £ m ;i Every part of an arch is ex¬ 
pressed or pushed by the other parts ; every part of a 
Cham is in a state of tension, or is pulled by the other 
parts. In many cases these forms are united. A girder 
consists of two mam pieces or booms, of which the upper 
one acts as an arch and is compressed, while the lower 
one acts as a chain and is pulled; and this is true even 
vhen both the pieces are quite straight. Thev are 
enabled to act in this way by being tied together, or 
nfiTWv * 18 Ca xi d ’ by c^'Pieces, which you must 
often have seen. Now, suppose that any good practical 
engineer makes a bridge or roof upon some approved 
pattern which has been made before, he designs the size 
and ■ shape of it to suit the opening which has to be 
spanned, selects his material according to the localitv 
assigns the strength which must be given to the several 
parts of the structure according to the load which it 
will have to bear. There is a great deal of thought in 
the making of this design, wiiose success is predicted 
by the apjilication of previous experience; it requires 
technical skill of a very high order, but it is not scien¬ 
tific thought. On the other hand, Mr. Fleming Jenkin 
designs a roof, consisting of two arches braced together, 
instead of an arch and a chain braced together, and 
although this form is quite different from any known 
structure, yet before it is built he assigns with accuracy 
the amount of material that must be put into every part 
of the structure in order to make it bear the required 
load, and this prediction may be trusted with perfect 
security. What is the natural comment upon this ? 
Why, that Mr. Fleming Jenkin is’a scientific engineer. 
Now it seems to me that the difference between scientific 
and merely technical thought, not only in these but 
in all other instances which I have considered, is just 
this. Both of them make use of experience to direct 
human action ; but while technical thought or skill en¬ 
ables a man to deal with the same circumstances that 
he has met with before, scientific thought enables 
him to deal with different circumstances that he 
has never met with before. But how, you will say, can 
experience of one thing enable us to deal with another 
qune different thing ? To answer this question we shall 
have to consider more closely the nature of scientific 
thought. 
Let us take another example. You know that if you 
make a dot on a piece of paper, and then hold a piece of 
Iceland spar over it, you will see not one dot, but two. 
A mineralogist, by measuring the angle of a crystal, 
can tell you whether or not it possesses this pro- 
perty without looking through it. He requires no 
scientific thought to do that. But Sir William Rowan 
Hamilton, the late AstronomerRoyal of Ireland, knowing 
these facts, and also an explanation of them which Fres¬ 
nel had given, thought about the subject, and he pre¬ 
dicted that,. by looking through certain crystals in a 
particular direction, we should see not two dots but a 
continuous circle. Mr. Lloyd made the experiment and 
saw the circle,, a result which had never been even 
suspected. This has always been considered one of the 
most signal instances of scientific thought in the domain 
1% sics.. It is not distinctly an application of ex- 
P?U ence gained under certain circumstances to entirely 
different circumstances. Now, suppose that the night 
before coming down to Brighton you had dreamed of a 
railway accident caused by the engine getting fright¬ 
ened at a flock, of sheep, and jumping suddenly back 
over all the carriages, the result of which was that your 
head was unfortunately cut off, so that you had to put 
it m your hat-box and take it back home to be mended. 
I here are, I fear, many persons even at this day who 
w ould tell you that after such a dream it was unwise to 
travel by railway to Brighton. This is a proposal that 
} ou should take experience gained while you are asleep, 
when.as the President says, you have no common sense, 
experience about a phantom railway, and apply it to 
guide you when you are awake, and have common sense, 
m your dealing with a real railway. And yet this pro¬ 
posal is not dictated by scientific thought. 
Now r let us take the great example of Biology. I pass 
over the process of classification, which itself requires a 
.great deal of scientific talk; in particular when a 
natuialist, 'who has studied and monographed a fauna or 
a flora, rather than a family, is able at once to pick out 
the distinguishing character required for the subdivision 
a ^. ord( r r fi u ^e new to him. Suppose that we possess 
all this.minute and comprehensive knowledge of plants 
and l l -^ Tnak and intermediate organisms, their affinities 
and. differences, their structure and functions; a vast body 
o experience, collected by incalculable labour and devo¬ 
tion. . I hen comes Mr. Herbert Spencer; he takes that 
expenence of life which is not human, which is apparently 
s a lonary, going on in exactly the same way from year 
o } car, and he applies that to tell us how to deal with the 
