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ery by which cotton and wool and silk are carded, spun and woven 
into the beautiful fabrics of the present day, is the product of the 
last one hundred and fifty years. It will be recollected by my 
friends who are now here that it was very doubtful towards the 
close of the eighteenth century whether cotton could be so treated 
as to separate it from the seeds, to be carded and spun into threads 
and woven into fabric; but while this doubt was threatening that 
great product of nature, Whitney gave us the cotton gin, . which 
separated successfully the seeds from the fibres of cotton, preparing 
it for the cards and introducing it through the gradually perfected 
machinery for drawing and spinning. 
The English inventors and factory men had their genius stimu- 
lated to the same end, and the spinning jenny, the mule, and the 
more elaborate machinery invented by Richard Arkwright, came 
into use, and, by improvements on the original structures, have 
_ arrived at the perfection with which our factories are now equipped 
and perform their work. 
If we turn to other branches of useful knowledge and of science, 
the first that make an impression on my mind are the wonderful 
discoveries in astronomy. ‘The old plan of searching the heavens 
by imperfect instruments has given place to the magnificent tele- 
scope of the present day. Photography has come in to the aid of 
the astronomer, and while his telescope searches out the stars and 
keeps his instrument in continued harmony with their motion, pho- 
tography copies the picture of the heavens and opens to us a world 
not only of knowledge but of imagination. 
The chemistry of the world has also undergone great changes. 
The middle of the eighteenth century was illustrated by the discov- 
ery of oxygen gas by Dr. Priestly, and that discovery influenced the 
science of chemistry to a very great extent in the early years of its 
progress. But Sir Humphrey Davy and the other later chemical 
philosophers found out that there were other supporters of combus- 
tion than oxygen, and by the combination of those other supporters 
of combustion we get the basis with which it is possible to combine 
those gases in the manufacture of important acids. 
The whole science of chemistry has been revolutionized, and now 
the chemists who survive and who received their instructions in the 
early years of the present century, not only cannot realize what the 
status of chemistry is at the present day, but are lost in amazement 
