i8 MATER i A MEDIC A AND THERAPEUTICS. 



1 fluid drachm = 0*003549 litre 3v549 c. centim. 

 1 minim = 0-000059 = 0-059 



and conversely : 



1 cubic centimetre 1-5-432 gi^ain measures. 



1 litre = 1 pint 15 oz. 2 drs. 11 min. 15432-348 



Domestic measures. A teaspoonful is a con- 

 venient but not quite accurate measure of 1 fluid 

 drachm ; a dessert-spoonful, of 2 fluid drachms ; a 

 table-spoonful, of half a fluid ounce ; a wineglassful, 

 of 1 J to 2 fluid ounces ; a teacupful, of 5 fluid ounces ; 

 a breakfastcupful, of 8 fluid ounces ; a tumblerful, 

 of 10 to 12 fluid ounces. Wherever accuracy is 

 desired, a graduated measure glass must be used. 

 Some " drops " being twice as large as others, it is 

 specially dangerous to order drops of powerful reme- 

 dies for children. 



Action and uses of drugs. The preceding 

 subjects complete the information furnished by the 

 Pharmacopoeia ; but the student must next make him- 

 self acquainted with the action and uses of each drug, 

 that is, its pharmacodynamical and therapeutical rela- 

 tions. In the following pages this portion of the 

 subject will be discussed under four distinct heads, 

 according to the order in which the drug affects the 

 different parts of the body. These are as follows : 



1. Immediate local action. When a medicine is 

 applied to an exposed surface, it may produce some 

 effect or " act upon " it. This may occur either exter- 

 nally, i.e. on the skin or exposed mucous surfaces, such 

 as the conjunctiva, anterior nares, vagina, etc. ; or inter- 

 nally on the alimentary canal, especially the stomach 

 and intestines, including the rectum. Some drugs 

 have no further action. 



2. Action in or on the blood. The great majority 

 of active remedies are absorbed into the blood, and 

 enter into the composition of its plasma, much less 



