Most of the potions specify clearly the quantity of each of the ingredients in the potion. They should be followed precisely. As I said in the Introduction lesson, as a beginner, you do not interfere with the quantities at all. In case you want to create more of a potion than the one in the recipe, each ingredient is increased directly proportional. If we want less, we decrease everything directly proportional.
The issue that needs to be discussed next is what happens when not all quantities are specified. The first thing to do is to establish which ingredients are active/main ingredients, and which ingredients are adjuvants or bases. In a future lesson, we will discuss the exact properties that make an ingredient to be main, adjuvant or base. For now, let's discuss the theory of the quantity.
1. Now, what do we do if a potion doesn't specify the quantity of one of the ingredients?
First of all, as I beginner, you should not attempt creating such a potion. So we only discuss this theoretically. If all quantities are specified, but one, it means it is the witch's choice how much of that ingredient he/she wants to put in the potion. Of course, you are supposed to use common sense when deciding upon a quantity. We will decide together upon a quantity of an ingredient in a potion, in order for you to get a better grip upon the "common sense" I was talking about.
Situation Number 1:
We have the "X Potion":
Active ingredient: 30 g
Adjuvant 1: 10 g
Adjuvant 2: 8 g
Adjuvant 3: unknown g
Base: 200 ml
When deciding upon an Adjuvant, we have to consider:
A. It should be less than the active ingredient.
B. It should be somewhere around the other adjuvants if the other adjuvants have a similar quantity.
Therefore, the correct answer would be: Adjuvant number 3 = between 6g - 10g
Situation Number 2:
We have an "X Potion":
Active ingredient: unknown ml
Adjuvant 1: 3 ml
Adjuvant 2: 2 ml
Adjuvant 3: 2 ml
Base: 15 g
When deciding upon an active ingredient:
A. It has to be less than the base in regards to volume.
B. It has to be more than the adjuvant with the higher volume.
Therefore, the correct answer would be: at least 4 ml if you want to be the least concentrated or more to increase its concentration, as long as its volume is less than the base.
Situation Number 3:
We have an "X Potion":
Active ingredient: 100 g
Adjuvant 1: 80 g
Adjuvant 2: 20 ml
Adjuvant 3: 80 g
Base: unknown g
When deciding for a base:
A. It has to be more than the active ingredient. Most of the times double the volume.
B. It has to be enough to incorporate both the active ingredient and the adjuvants. But not too much, otherwise it is going to be way too diluted.
Therefore, the correct answer would be a minimum of 425 ml (3 cups) and a maximum of 600 ml.
The theories above stand even when more than one ingredient is missing.
2. What would we do when none of the quantities is specified?
Well, it would obviously mean that we clearly need to find out two things:
a. Which is/are the main ingredients? Which ones are the adjuvants? Which is/are the bases?
b. The way the potion is to be administered. Is it a drinkable or a non-drinkable potion? Instant or long-term? etc.
When you create such a potion, deciding on the quantities can be a really hard and long process. And even someone very experimented can mess it up. This is why a potion as such needs to be tested first on a smaller case and the side effects and the general effects to be noted. And maybe sometimes the potion to be remade. The general rules still apply, but in such a situation, everything is really tricky.
II. Measuring tools:
In magic, we do not only measure the quantities of the ingredients. Many potions, for example, require to have a certain temperature to be prepared/drunk or even be brewed for a certain amount of time, etc. Therefore we need quite a set of measuring tools.
A. Noted cups (in order to measure liquids)
B. Measuring spoons
C. Cooking Thermometers (not regular ones, mercury can be dangerous and interact with the potion)
E. Measured shot glass (for potions containing liquids which need to be measured in ml)
Observations: Because there are more than one systems of measurement in the world, you may notice sometimes that you will encounter quantity units you do not know about. Use a good online converter. To be on the safe side, try two online converters, just to check if everything is properly converted.