Seg... imiplietty oath seein, as eras ehehinsal all 
ject of the prescription. — Nothing ought to enter into the com 
tion which does not add to its virtue, render it less ungrateful, 
__ it a convenient form, or what is not necessary to conceal any part 
_ Tar ingredient; and in general, the practice of ‘accumulating a a a aa 
ber of articles in one prescription is to be avoided. 
2dly. Substances, it is evident, ought not to be mixed together, - 
which are capable of entering into chemical combination, or of ae.” 
composing each other, utiless it be with the view of obtaining the 
product of the combination, or decomposition, as a remedy. ~~ 
3dly. Those mixtures are also to be efeided jn which one medi- 
cine By its peculiar action on the stomach, modifies and c! 
~ action usually exerted by another, unless where the object is oS at at 
3 — the effects of that modified operation. ge 
_  4thly. The error of contra-indication is to be guarded against, o 
those medicines ought not to be combined, the virtues of which are 
not merely different, but are in some measure opposed to each | ; 
| -5thly. The ingredients which are to be mixed must be su 
will mix properly together, so that the form in wh 
designed to be exhibited, may be easily obtained 
Lastly, The form under which a medicine is - 
adapted to certain circumstances ; principally to the nature 
ease, the nature of the remedy itself, and as far as may be possible, | 
to the taste of the patient. 
The doses of medicine are not reducible to any general rales, 
from their general similarity of operation, or any other cire imstan 
The principal circumstances by Which they are influenc 1 are, age, 
sex, temperament, idisyncrasy, habit, and disease. _ 
Age—From infancy to manhood, a larger dose of any iedieae 
is requisite to produce its effect, in proportion to the advance in life. 
From manhood to old age there is a similar gradation with regard to 
diminution of dose, though in much less proportion than that which 
regulates the increase. The following table has been ppm to 
shew these proportions. = 
TABLE. 
ot the dose for a person of middle age be - 1 or 1 drachm. 
For one from xiy. to xxi. years it will be - 2 or 2 scruples. 
from vii. to xiv. - - - i or half a drachm. 
——- from iv. to vii. - ee - : or Papen 
——ofiv. yearsofage - - = or 15 grains. 
——— of iii. ses ofage = - 5,4 H or half i 
—— of ii. years ofage - or Ss - }or8 grains. = 
—— ofi. year ofage - - ores ty or 5 grains. 
—— of 7 weeks old . - - zz or 4 grains. 
Sex.—Women, in general, require smaller doses of any medicine 
than men, a difference probably owing to their greatest sens 2 
ym their habits of life. ni am = 
