主题：【讨论】美国药典中的 1 drop (medical or metric drop?)

(小弟可勉强看懂简体汉字，但用键盘输入汉字则很因难。以下用英文或中英混合表述，请谅。)

When I clicked [回复] to reply the post【求助】美国药典中的1 drop是什么意思啊, a warning popped up, but I could not understand the words because they were a group of 乱码.  I therefore made a new post.

I searched the information regarding “美国药典中的1 drop是什么” from Google by inputting the keywords “drop, unit”, and found that the “metric drop” is different from the “medical drop”; however, they may have been unified now, I have no idea.  The information is copied as follows for your information:

The drop is a unit of measure of volume, the amount dispensed as one drop from a dropper. It is often used in giving quantities of liquid drugs to patients, and occasionally in cooking.
The volume of a drop is not well-defined: it depends on the device and technique used to produce the drop and on the physical properties of the fluid. This is similar to units like the cup, tablespoon, and teaspoon that depend on the spoon or cup.
There are several exact definitions of a "drop":
·    the "metric" drop, 1/20 mL (50 μL).
·    the medical drop, 1/12 mL (83 1/3 μL).
·    the Imperial drop, 1/36 of a fluidram (1/288 of an Imperial fluid ounce, or 1/1440 of a gill) (approximately 99 μL).
·    an alternate, possibly apocryphal, definition of the drop is 1/1824 of a gill (approximately 78 μL).
·    the U.S. drop, 1/60 of a teaspoon or 1/360 of a U.S. fluid ounce (approximately 82 μL).
·    an alternate definition of the U.S. drop is 1/76 of a teaspoon or 1/456 US fl oz (approximately 65 μL).
According to Webster dictionary, "drop" indicates the smallest volume of a liquid that may be measured. The size of drop may vary with the viscosity of the liquid.
In the past, a drop was another name for a minim. This meaning was used in Pharmacy to describe a volume equal to one 60th of a fluid dram or one 480th of a fluid ounce. This is equal to about 0.0616mL (U.S.) or 0.0592mL (Britain). Pharmacists have since moved to metric measurements, with a drop being rounded to exactly 0.05mL (that is, 20 drops per millilitre). In hospitals, intravenous tubing is used to deliver medication in drops of various sizes ranging from 10 drops/mL to 60 drops/mL. A drop is abbreviated gt, with gtt used for the plural. These abbreviations come from the Latin for drop, gutta.[1] articles.
A drop can also be used less formally as a unit of volume in recipes. According to some older kitchen references, 24 drops = ¼ teaspoon. Using U.S. definitions, this makes the drop equal to about 0.051mL, making it quite comparable to the pharmacist's drop.[1]
1.    ^ a b Russ Rowlett. How Many? A Dictionary of Units of Measurement. University of North Carolina (2005-17-11). Retrieved on 2006-09-07.
Retrieved from "http://en.wikipedia.org/wiki/Drop_%28unit%29"