foreign to this class. As anthelmintics they 
produce the following effects. They kill 
worms to which they come to be applied in 
the body. They expel them from tlie body. 
They prevent their generation in the body. 
The only changes produced in the system, 
that are here to be considered, are those 
which arise from their action upon the worms 
themselves. These are, the removal of an 
almost infinite variety of different symp- 
toms which worms produce whilst lodged 
in the body. Anthelmintics may be sub- 
divided into the following tribes : poiso7ious, 
as quicksilver, tin, sulphur; lubricant, as 
oil of olives and oil of linseed; tonic, as sa- 
vin, tansy, santonicum ; cathartic, as scam- 
mony, jalap, aloes, gamboge. Their indi- 
cations are raani.tested from the following 
con.siderations ; 1. From their action on the 
worms themselves ; whence tliey may be 
employed to kill worms lodged iu different 
parts of the human body. 2. From their 
action on the system; whence they may 
be used to jMomote the expulsion of worms 
from the body, whether dead or alive ; to 
prevent the generation of worms in the 
body. These indications may be illustrated 
and confirmed from practical observations 
concerning the use of anthelmintics in cases 
of atrophy, diarrhora, and vomiting. 
The cautions to be observed in the em- 
ployment of anthelmintics, as derived from 
their nature, chiefly respect the other ef- 
fects they have upon the system, indepen- 
dent of their action as anthelmintics. The 
conditions of tire system which chiefly re- 
quire attention in their employment are in- 
fancy, delicacy of habit, and other similar 
affections. In the regimen farinaceous 
food should be avoided ; and exercise should 
be encouraged. 
There are, perhaps, no morbid conditions 
of the system, during which the removal of 
worms from the body may not with pro- 
priety be attempted by one mean or othei'. 
But, although it may be doubtful whether 
there be morbid conditions contra-indicat- 
ing the whole class, yet it cannot be ques- 
tioned that there are many contra-indicat- 
ing particular orders. Among otheis may 
be mentioned: an abraded or inflamed 
state of the intestines, contra-indicating the 
poisonous ; accumulations of feces in the 
first passages, contra-indicating the lubri- 
cant ; a peculiar sensibility of the stomach, 
contra-indicaling the tonic; and topical in- 
flammation of the intestines, previous loose- 
ness, or a high degree of inanition, contra- 
indicating the cathartic. 
17. Absorbents. 
This term is used differently by different 
therapeutists. Generally speaking, it im- 
plies medicines which, possessing no acri- 
mony in themselves, possess, notwithstand- 
ing, a power of destroying acidities in the 
stomach and bowels: at other times, how- 
ever-, it is employed more largely to indi- 
cate those substances, as well, which in- 
crease the genei'al action of the absorbent 
system. They may hence be divided into 
two kinds : the calcareous, as burnt harts- 
horn, oyster shells, and chalk ; and stimula- 
tive, as burnt sponge, salt of hartshorn, 
and alkalies. They are hence indicated in 
peculiar acrimonies, or peculiar torpidities 
of the system generally, or particular or- 
gans of the system ; and may hence be em- 
ployed beneticially in acidities of the sto- 
mach, heartburn, and excesses in a vinous 
potation ; as well as in strumous and other 
leiicophlegmatic affections of Ihe glandular 
system; especially in bronchocele, or the 
disease termed provincially Derbyshire- 
neck, and scirrhosities of either extremity of 
the stomach. Their use may be collected 
from practical attention to these diseases, in 
which, notwithstanding, they commonly re- 
quire to be connected with more active 
applications. On this last account they 
may generally be employed without appre- 
hension : yet in cases of acidity of the sto- 
mach, they have often been used to an ex- 
tent that has produced worse diseases than 
the malady they were intended to remedy, 
and have laid the foundation for calcareous 
concretions, that have resisted the applica- 
tion of almost every purgative, and formed 
indurations almost as troublesome as the 
calcareous concretions of the bladder : con- 
cretions which have only been removed by 
a long use of active lithontriptics. 
MATHEMATICAL instruments. Under 
this term we shall treat of the instruments 
usually sold in cases, and made on a port- 
able plan, so as to fold up into a small 
space, to be cai-ried in the pocket with- 
out injury to any part. These cases are 
made either vertical, or hoiizontal ; but the 
latter mode is far preferable, although the 
bulk is, in this form, somewhat augmented, 
because the points are kept in a better 
state of security; an object of the utmost 
importance to the mathematician ; since 
the excellence of the compasses, and draw- 
ing pens in particular, will, in a great mea- 
sure, depend upon the delicacy of their 
terminations. The whole of the steel-work 
in a case of instruments should be of the 
