Plants - Drugs Mind - Spirit Freedom - Law Arts - Culture Library  
Review Erowid at!
Help us be a "Top Rated Nonprofit" for the 10th year in a row
and spread info about psychoactive drugs, health, culture, & policies.
("Share Your Story" link. Needs quick login creation but no verification of contact info)
Liquid Measurement Technique
by Erowid

  1. Liquid Measurement Tech, by Zam
  2. Excellent Measuring Technique for Exotic Compounds, by The Lion
  3. Issues with Liquid Measurements
    1. Starting with a Known Dose
    2. Solvents Can Affect Seals
    3. Evaporation
    4. Freezing
  4. Third Plateau's Psychedelic Booze Instructions
  5. Volumetric Calculator at Tripsit

Liquid Measurement Tech
by Zam

with contributions & suggestions by others, HTML & editing by Erowid

Many psychoactives have doses in the 5-100 mg range. Few people have access to scales capable of measuring quantities that small, and buying one can be very expensive. The Liquid Measurement Technique is a powerful way to measure small amounts of chemicals very accurately. It consists of using a scale to measure a larger amount of a substance very accurately and then mixing this substance with a known amount of liquid. The dissolved substance in liquid form can then be administered much more accurately using a dropper or syringe. By using a liquid measurement technique, it is possible to use a 30$ scale and still measure accurately to only a few milligrams.

  • A scale accurate enough to measure very accurately the amount of material you want to break up into smaller doses.
  • A storage bottle appropriate to the chemical & solvent.
  • Solvent appropriate to the chemical (water, ethanol, acetone, dichlor, etc)
  • Liquid Measurement device: Eye dropper and/or small graduated syringe
  • Substance to be measured
  • A sticky label for the bottle or paper & clear tape.
  • A calculator, pencil & paper

The simplest way to do this is to use a standard extract dropper bottle sold at any 'health food' store, water, and a small syringe (1-20cc).

Choosing a solvent:
Choosing a solvent can be tricky if you don't know what's appropriate to the substance. Distilled water is the preferred type of water. Chlorinated tap water is almost always a mistake. Some substances don't dissolve well in water and can precipitate out over time. Some chemicals will dissolve in warm water and water can be used for immediate measurement, but not for storage. Some solvents will also degrade over time when stored in water. If you're working with a new substance, probably don't dissolve all of it at once.

Each solvent & chemical combination's solubility will also affect how much material mass will dissolve in each milliliter of the solvent. You can't fit 1 gram of sucrose into 1 drop of water.

Calibrating The Dropper:
If you're using an eye-dropper, first the dropper needs to be calibrated. Although droplets of a particular solvent tend to be very similarly sized between drops, they vary from one dropper to another and vary some between drops, so its very important to calibrate the particular dropper you're using.

Water tends to drop from small droppers at about 15-25 drops per milliliter. The simplest way to calibrate a dropper is to use the dropper bottle that you will be using and fill it using a graduated syringe so you know exactly how much water (or other solvent) you put in. If a 20 ml dropper bottle was to be used, a syringe can be used to measure exactly 20 ml of water into the bottle and then the dropper is used to move all of the liquid from the bottle into another container and each drop is counted. Record the total number of drops and divide by the number of milliliters you started with. This gets you the number of drops per milliliter. This takes time and should be done several times to get an accurate count of how many drops the dropper you're using has per milliliter. The number of drops per milliliter will very likely vary by 10-20% depending on how you squeeze it and other seemingly random variations.

If a syringe is used to measure the liquid, the calibration should be done for you. 1cc syringes are very good for this, but aren't as convenient to carry or store as a self-contained dropper bottle.

For this walkthrough, lets assume a 20 ml dropper bottle that has between 15-18 drops per milliliter.

Measuring the Material:
The material has to be measured accurately, so you know how much you're working from. The benefit of liquid measurement is that it allows you to measure many times the increment you intend to administer so that it can be done with less costly equipment and much more accurately. If you wanted to measure out 5 mg of a substance, for instance, you could weigh out 100 mg very accurately with a good scale, dissolve in a liquid and then take 1/20 of the resulting solution.

Measure a chosen amount to be weighed and weigh it very carefully. Record the total mass of the starting material.

For this example, lets assume 100 mg of starting material is accurately weighed on a .002 mg readable balance on a rock solid table that has been levelled properly.

Determining the Amount of Liquid:
At this point, its important to figure out how accurate the measurement needs to be. If you're working with a material where you only need to be +/- 5 mg you will not need as much liquid per mg of material than if you need to be accurate to .010 mg. You will need to use enough liquid so that each increment of liquid that you can measure accurately doesn't contain enough of the target chemical to be a problem. If you had a substance that needed to be accurate to within +/- 1 mg and you're using a dropper that has 15-18 drops per milliliter it would be inappropriate to make a solution where 1 drop = 1 mg of material because you're not likely to get reliable results, your hand can slip as you squeeze the dropper etc.

A rule of thumb is to figure at least a factor of 10 between the minimum liquid measuring increment (in the case of a dropper, thats 1 drop) and the minimum required accuracy for the substance you're dissolving. Lets say you're working with a substance (such as DOB) where you wanted to be accurate within .1 mg and you're using a dropper bottle. The Order of Magnitude Rule of Thumb would suggest at least 10 drops per .1 mg or 100drops per milligram. With our example dropper, that would be about 6ml per milligram and so only 3+ mg would fit in the entire bottle. This level of control would allow you to actually administer with reasonable accuracy to .05 mg (about 5 drops) and is probably far more than is actually required. Perhaps you re-think this and decide that what you really want it to be absolutely sure you are within .5 mg with the DOB, so you change to 10 drops per .5 mg and thus 20 drops per milligram. This allows the example 20 ml dropper to hold about 17 mg of DOB, which is a good amount of DOB: not enough to necessarily make all your limbs fall off & kill you if you took the whole thing at once and enough to be able to have multiple doses in a single container.

For this example, lets say that we have a material for which +/- 1 mg is no big deal (something like 2CB), so perhaps our target accuracy is 2 mg. We Rule of 10 Thumbs this to get 10 drops per 2 mg, or 5drops per milligram. That would allow me to put ~68 mg of material in the 20 ml bottle ( ( 17 drops per ml / 5 drops per milligram ) * 20 ml in bottle ). I think I'd rather reduce the accuracy a little and get more in the bottle, so I decide to go with 2 drops per milligram which will reduce my target accuracy quite a bit, but its still fine. If I slip and accidentally get an extra couple milligrams of 2CB, I'll survive. At 2 drops per milligram, that means 7-8 milligrams per milliliter (15-18 drops per milliliter for the example dropper). That means that about 150 milligrams in my 20 ml dropper bottle. Thats a good amount and 2CB is nice and stable in distilled water.

Another consideration when you're choosing a concentration is to think in terms of Fail Safe. Fail Safe means that when a system fails, it should fail in a way that isn't catastrophic to other systems. For liquid measurement, that means to think in terms of the tools you'll be using. If you are using an eye dropper, the obvious thing is that you might squeeze the whole dropper at one time by accident. Don't ever setup your tool so that you could accidentally administer a dangerous dose. You don't really need to be able to carry 100 doses with you. Keep the rest in a larger reserve bottle that you refill the administration bottle with.

Record the concentration & the number of drops per milligram.

Test Solubility:
If this is your first time with this substance and solvent, verify the substance is soluble in the solvent you've chosen (in the example, water). Take a small amount of material and dissolve it in a small amount of the solvent. If it won't dissolve, you may need to change solvents.

Mix Solution:
After you have the substance measured and the liquid measured, the two are combined in the storage bottle and shaken or mixed until no solid remains. After the bottle sits for a while make sure there is no precipitate forming as this could substantially change the concentration and the dropper or syringe could get chunks, which could drastically change the dose administered.

Make A Label:
Print the substance, the number of drops per milliliter from this dropper, the number of milligrams of material per drop and number of milligrams per milliliter clearly on a label for the bottle. Write the type of solvent on the label. Mislabelling illegal substances may seem like a good idea, but its not. Its surprisingly easy to forget and its surprisingly easy for someone else to take the label for whatever it says. If you can't write the name of the substance itself, use a code and write "Not For Internal Use" on the label.

Evaporating to a solid:
Although many salts & compounds can be easily dissolved in water or alcohol and administered as a liquid, many solvents are completely inappropriate for ingestion. The liquid measurement technique can also be used to take the resulting measured liquid that contains the substance and drying it on a glass or ceramic plate until the substance remains as a powder. The powder can then be scraped up and encapsulated.

Evaporating onto blotter:
The liquid measurement and evaporation technique is the very common way that LSD blotter is made, by making a liquid of known concentration and then either dripping onto squares or soaking sheets of paper in the liquid and then drying. The chemical is deposited on the paper. Many users of liquid LSD use this process informally to make it more transportable: putting a drop on a piece of paper and letting it dry to carry instead of the vial.

Liquid measured chemicals can also be deposited on paper formally by doing a series of tests on the target blotter paper to see how much chemical the blotter can easily absorb before crystals or material is left on the surface. The liquid measured substance can then have very accurately set doses soaked onto blotter paper and the resulting material is more easily transported. Blotter-deposited materials, however, usually have much worse shelf lives due to huge surface areas exposed to air and are often handled very casually. pH neutral, acid free, non reactive blotter paper is generally preferred. Typing paper and brown paper don't absorb much and may have other properties and dyes that could react with chemicals in unexpected ways. Evaporating onto paper works best for very low dose substances (such as LSD or DOB) and should not be used for storage.

Excellent Measuring and Storage Technique for Exotic Compounds
By The Lion

In an effort to simplify and streamline the handling, measuring, and storage of various exotic powders I developed a nice method that allows easy handling and accurate measuring without the use of a sensitive scale. This method can be applied in many myriad of different ways, but I have found the standard dropper bottle format to be my favourite easy all around packaging vehicle.

Using a 1oz amber glass dropper bottle (acquired at a health food store) I first measured the number of drops per dropper. This was accomplished by giving one thorough squeeze to the bulb and sucking up as much liquid as possible. My particular dropper came out to approximately 30 drops per dropper full of liquid.

Starting with a known quantity of 1g of exotic powder, I determined that I wanted to calibrate the mixture to 1 mg of active material for each drop. I then calculate that I would need approximately 33.3 droppers full of liquid to achieve the correct ratio. (1000 mg of active powder divided by 30 drops per dropper equals 33.3 droppers full required to be added to the mix.)

Carefully place the 1g of powder into the clean empty dropper bottle and add 33.3 droppers full of vodka or everclear. You now have a 1oz bottle full of a calibrated alcohol solution that is equivalent to 1 mg per drop. Using alcohol as your carrier will allow you to store your bottles in the freezer which will typically maintain the integrity of the active compound for a very long time. Be sure to properly label your new bottle with compound and calibration information. Depending on the solubility of the compound, you may need to lightly warm the outside of the bottle using a hot water bath to get the crystals to go into solution.

The Lion

Starting with a Known Quantity

One potential problem that arises when people plan to use a liquid measurement technique for measuring individual doses, is figuring out how much material one is starting with. It is imperative that the material being dissolved be accurately measured. Some people figure if they buy a quantity of material from a vendor or individual, the amount of material they receive is known. This Is Not The Case. For instance with legal, grey market, or research chemicals, it is not uncommon for a vendor to provide significantly more or less material than the amount ordered. One individual describes ordering 500 mg of a compound only to measure it when it arrived, finding 1000 mg instead. If s/he had assumed that the starting material was 500 mg, and proceeded to use a liquid measurement technique to measure individual doses, those doses would have been twice as strong as intended.

Initial material must be measured. The point of this technique is to be able to measure small amounts accurately, not to be able to measure an unknown quantity of material.

Solvents Can Affect Seals

Another issue to look out for: If you are using a non-polar solvent, many of the seals and caps on standard dropper bottles may degrade with the solvent. I've seen first hand that not all plastics are created equal. If you buy storage bottles from chemical supply houses or vendors, you can make sure to get plastic seals that are appopriate for the type of solvent you're using.

Evaporation Issue

Another possible pitfall when storing substances dissolved in solvents the chance that overtime & when the container is opened, some solvent may evaporate and throw off the accuracy of the measurement. How much this matters depends on how concentrated the substance is in the liquid and how much difference small changes in volume will make to the overall dose. For LSD or DOB dissolved in etoh or other solvent this could become a real problem. Each exposure to air will no doubt allow a small amount of etoh to evaporate and concentrate the solution just a tad. Most bottles don't seal perfectly and over time the solvent will eventually dry out.

For long storage of materials in liquid form, bottles should be marked with level at which they were stowed so any change can be noted. A log book can be used to minimize confusion. Just something to keep in mind.


If you plan on storing your liquids frozen or very cold, be careful about using water. It can expand when its frozen and break the bottle or break / open the seal so that the material is exposed.