IMPORTANCE OP THE STUDY OF CHEMISTRY. 
47 
Indian hemp a place among the so-called hypnotic medicines, 
next to opium ; its effects are less intense, and the excretions 
are not so much suppressed by it. Digestion is not disturbed, 
the appetite rather increased, sickness of the stomach seldom 
induced, congestions never. Hemp may consequently be 
employed in inflammatory conditions. It disturbs the ex¬ 
pectoration far less than opium. The nervous system is also 
not so much affected. The whole effect of hemp being less 
violent, and producing a more natural sleep, without inter¬ 
fering with the actions of the internal organs, it is certainly 
often preferable to opium, although it is not equal to that 
drug in strength and reliability. An alternating course of 
opium and Indian hemp seems particularly adapted to those 
cases where opium alone fails in producing the desired effect. 
—Prayer Vierteljahrschri/t , xvii, I860; and North-American 
Medico- Chirurgical Review. 
ON THE IMPORTANCE OE THE STUDY OE CHEMISTRY. 
By A. W. Hofmann, LL.D., F.R.S. 
Dr. Hofmann in a lecture on this subject, lately delivered 
at the South Kensington Museum took as principally illustra¬ 
tive, the influence that the manufacture of sulphuric acid and 
coal gas has exerted on the progress of civilization. 
To those who have not given the subject consideration, 
they will be surprised to see how these two branches of in¬ 
dustry ramify, and the results that have unexpectedly followed. 
He says: 
In taking a retrospect of the rapid progress which some of the arts and 
manufactures, depending upon chemistry, have made in modern times, we 
are at a loss to know where to begin our survey, every branch of industry 
could furnish the most brilliant illustrations. Were I to trace with you 
the history of sulphuric acid, from the moment when the Erfurt monastery 
first witnessed oil of vitriol passing over, drop by drop, from the alembic of 
Basilius Valentinus, up to the present time, when hundreds of thousands of 
tons are sent forth from the colossal lead-chambers of Great Britain alone; 
were I to enlarge on the influence which chemistry, by raising the production 
of sulphuric acid to its present degree of perfection, has exerted on the 
development of chemical manufactures; were I to describe the action of 
sulphuric acid in the preparation of the other acids, of nitric, hydrochloric, 
of acetic acid; its application in the manufacture of phosphorus, its em¬ 
ployment in the improved process of candle-making, in the isolation of 
stearin from crude tallow, its use by the dyer for preparing his colours, by 
the skin-dresser for opening the pores of the skin previous to the operation 
of tanning; by the metallurgist in the new process of refining silver; by 
