62 Hofmann and Modern Chemistry. | Jan., 
midst of the mental strife, it is as difficult to discover the real order 
of progress, as it is for the soldier on the battle-field to learn the 
fortune of the day. We can, however, examine the road over 
which we have passed, can remember the names of the great men 
who have left their footprints deeply impressed for our guidance ; 
and gathering experience from the teachings of the past, we may 
venture to predicate how the future will regard the present. 
The science of Chemistry specially claims our attention at this 
time, as ministering extensively to the requirements of man, and 
adding greatly to his knowledge of natural phenomena. 
At the commencement of the eighteenth century, Stahl put 
forward his doctrine of Phlogiston, for which, perhaps, the road had 
been prepared by Mayow.* A phlogistic system, however, was the 
dawn of a new day, and the rude empiricism of previous time 
perished before its hght. The spirit of mquiry which arose upon 
the promulgation of this hypothesis gradually took form, and in 
1777 we find Sx Torbern Bergman writing these remarkable 
words :— 
“We have no knowledge of bodies @ priorz: every intelligence 
about them must be acquired by proper observations and experi- 
ments. But to discover and pursue such experiments, as really 
illustrate the point we are in search of, requires not only skill and a 
peculiar application, but also the most impartial love of truth; m 
order not to be ensnared by the pleasing desire of drawing general 
conclusions from a few data of precarious certainty. It lessens, no 
doubt, our trouble, and flatters our vanity, to be able to disclose in 
a moment the whole course of nature. Man is besides naturally 
indolent, and much inclined to be captivated by imagination more 
than by reality. The confession, therefore, that we really know no 
more than what we know, is,—even in our days when the experi- 
mental method is considered as the only right and true method,— 
very difficult and humiliating.”+ 
Scheele, Lavoisier, and Priestly were, however, the first who 
introduced the exactness of Physics—the system of observation by 
weight and measure—into Chemistry ; and from their times it may 
be regarded as a new science. These philosophers gave the world 
many truths as the result of their modes of investigating nature, 
and one of them, Lavoisier, taught a chemical nomenclature, which 
has aided, to the present day, in the ever difficult task of expressing 
new ideas in a form of words which shall convey a correct im- 
pression to the mind. 
Prior to, and indeed for some time after this period, although 
* ‘Opera Omnia Medico-physica, Hage, 1681.’ 8yvo. ‘ Dissertatione de Res- 
piratione ;’ and also, Mayow’s Diss de Salnitro and Spiritu Nitri Aereo.’ 
+ ‘Prefatory Introduction to Chemical Observations and Experiments on Air 
and Fire. By Charles William Scheele. Translated by J. R. Forster, LL.D., 
F.R.S., &e. 1780. 
