PRESCRIPTION WRITING 



89 



A drop is often used synouymously with minim, which 

 is correct if the substance spoken of is water, or a liquid of 

 nearly similar density. If the liquid is not of similar den- 

 sity, then a minim, or the sixtieth part of a drachm, is far 

 from being a drop as measured by dropping a liquid from 

 any ordinary utensil. Any amount from 45 drops to 276 

 drops, measured in this way, may be obtained from a 

 drachm of fluid, according to its density, mode of dropping, 

 and kind of vessel from which it is dropped. 



A gutta (gti), then, is of no fixed value, but means a 

 drop as dropped from a vessel; while a minim is always the 

 sixtieth part of a drachm. 



RELATIVE VALUE OF UNITS IN THE WINE MEASURE. 



The abbreviation, FL, is usually omitted in prescription 

 writing, as referring to fluids, the character of the prepara- 

 tion being sufficiently apparent. The Roman numerals are 

 used to express the quantities employed. The Roman 

 numerals are written under a horizontal line, the i's or j's 

 are dotted (they are identical in Latin) and the dot serves 

 to enforce and check the numbers used. Fractions are 



