Why does Holmes have test tubes of coloured liquids in his lab?

In the latest series of Sherlock Holmes, there are often little phials of coloured liquids in his lab., into which someone has dropped a piece of dry ice, bubbling away. What would be the point of that then?Why does Holmes have test tubes of coloured liquids in his lab?
Dramatic effect !





Also, Holmes was (fictionally) addicted to various narcotics, so he may be cooking-up something for himself.





Hope this helps :)Why does Holmes have test tubes of coloured liquids in his lab?
Dramatic effect !





Also, Holmes was (fictionally) addicted to various narcotics, so he may be cooking-up something for himself.
The dark theme underlying the Sherlock Holmes stories is that he is a cocaine addict. He's probably preparing his own crack.