well many opiate compounds readily crystalize, --into powders of white, yellow, tan-depending on purity. They just as readily dissolve into water or alcohol (for water, you often need to apply some heat.)
heroin is a good example--sold as a whitish powder that looks like 10X(confectioners) sugar, it can be disolved in a teaspoon of water with the heat of a match (a junk's 'works' often include a spoon.) if needed, they will use scrapes of tin foil- but its easier to extract all the liquified heroin out of a spoon.
Morphine was often shipped out as small vials of powder too, to which a small about of hot sterile water was added to 'reconstitute' it. (i think it has a longer shelf life as powder)
i think (just a WAG)that heroin, and other opiates disolve more readily in alcohol. which was used along with sugar and flavorings) to make 'tinctures' --syrupy like liquids.
most opiates are bitter to taste, naturaly. needless to say they were very addictive!
your stomach (the acid) and your liver, are remarkable effecient at removing the opiate compounds from your blood system, so the 'high' of ingested compounds is much 'lower'.
Mainlining (injecting into a vein) is a much more effective way to introduce drugs.
an alternate method was practiced in mediaval europe and in the americas--enimas! the indians of Central america had ritual enimas, with cocaine and marijuana compounds infused into alcohol, and then administered rectally. in europe, opium paste (raw poppy juice) was mixed with herbs, and used by woman as dildoes--stories about women 'riding high' on broomsticks have an element of truth!
in both cases, the drugs were applied not to skin, but to what i know as 'mucous membranes' (semi skin that is wet) the inside of your mouth, nostril, inside eyelids would be others. inhaling (snorting) cocaine through the nose is still practiced, and for the same reason. mucous membranes allow many chemicals to pass through (regualar skin resist such transfers)
there was a interesting article about central american enima practices about 2 years ago in NATURAL HISTORYmagazine.
Laudanum
