Carbolic soap

 The hand wash in my bathroom has run out. Then I remembered that we bought some carbolic soap from the a museum last year. It stinks! https://en.wikipedia.org/wiki/Carbolic_soap It is a noted anti-septic but the warning is that it could be a skin irritant.

 I had an idea that it contains carbolic acid so I decided to test it with my red cabbage indicator. I shaved some bits of soap of and made a weak watery solution of it, which was pink like the soap.

Then I added the red cabbage indicator. The result is actually an alkali, as is the case with soap. Searching around, it is likely that the carbolic acid (phenol) is reacting with the fats used and making a slightly alkaline product. This is Chemistry, though, so not my main subject. https://en.wikipedia.org/wiki/Phenol has the interesting anecdote that it was its early use in sewage treatment in Carlisle that alerted Lister to its possible use as an antiseptic. It seems that in Carlisle it all about the smell.