PRESIDENTIAL ADDRESS. 539 
while to a successful trader it may be a source of daily satisfaction. Scienees 
vannot be dismal or wicked; it is only men that can be joyful or desponding, or 
good or bad. 
Having thus endeavoured to the best of my ability to protest against the 
idea that economics is not a science, but a mere collection of copybook 
aphorisms that may be used at random like quack medicines, I should like, with 
your leave, to endeavour to establish its claim to come among the exact sciences 
by the surest test that can be applied—namely, its capability of being demon- 
strated by means of geometry and mathematics. 
I know that here I touch on delicate ground. I fear that there are many 
to whom the very name of geometry is repellent. The cause of this generally 
is that in their youth mathematics was presented to them in a totally indiges- 
tible form. It was like a vegetable diet is to a cat—the intestine was 
unfitted to assimilate it. I would, however, ask such persons, if any of them 
be here, to exercise their sense of fairness) How many boys who are totally 
incapable of comprehending any poetic idea are subjected to a steady course 
of English poetry in the Board Schools, and of Latin poetry in the public 
schools. The process is painful, but it is believed to do them good. Seeing, 
then, that I am, so to speak, in the pulpit for a short time, I will ask those 
who dislike mathematical reasonings patiently to listen in their turn while I 
try to expound the doctrines of supply and demand in a geometrical form— 
a form familiar, I have no doubt, to many of my audience, but very useful to 
illustrate my present theme; a form first designed by Cournot, but subsequently 
developed by other workers. 
I will commence by saying that for the comprehension of this method no 
previous acquaintance with mathematics or geometry is necessary. One can 
work straight from first principles, and this mode of considering the problem 
has been so helpful to many persons that I believe it will find favour in the 
eyes even of opponents. Moreoyer, in so far as it is correct, it certainly helps 
to prove the proposition with which I started, that economics may claim to have 
entered upon the-positive stage.e 
Everyone in this room is no doubt acquainted with the machine known as a 
barograph or registering barometer. There is one on the table. It is con- 
structed as follows: A vertical cylinder covered with white paper revolves 
once in a week. A light arm is hinged on to a series of hollow elastic circular 
chambers, from which the air has been pumped out. As the pressure of the 
atmosphere varies, the air chambers dilate and contract, carrying the arm with 
them. The arm carries a pen which marks with a dot on the paper the height 
of the barometer at any time. As the paper moves the dot is drawn out into 
a line, which gives a continuous record of barometric variations. This diagram 
is a picture of one of the records. 
_ Now, a little consideration will show what a useful diagram we have here. 
If we were to attempt to give the information contained in it in words we 
should have to say something like this. On Monday at 0 a.m. the barometer 
stood at 28.8 inches; during the morning of Monday it rose until about 2 p.m., 
when it remained stationary for three hours. It again steadily rose in the 
evening, until at midnight it stood at 29.9 inches (fig. 1). On Tuesday it still 
continued to rise till midday, when it again experienced a fall, &c., &c. Or, if 
