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Without litmus paper or a pH indicator, you can still test for acidity or alkalinity by observing how a substance affects certain natural indicators. For example, red cabbage juice will turn reddish in an acid and greenish-yellow in a base, while turmeric will turn brick red when added to a base, and remain yellow when added to an acid. 

Here's a more detailed explanation:

1. Using Natural Indicators:

• Red Cabbage Juice:

  Red cabbage juice can be used as a natural indicator. When an acid is added, it will turn the juice a reddish color, and when a base is added, it will turn the juice a greenish-yellow.

  
  

• Turmeric:

  Turmeric is another natural indicator. When added to a solution, it will turn brick red in the presence of a base, and remain yellow when added to an acid. 

  
  

2. Observing Other Properties:

• Taste: While not recommended for all substances, some acids have a sour taste (like lemon juice) and some bases have a bitter or soapy taste. However, this method is not safe for all substances and should be used with caution.

  
  

• Feel: Bases often feel slippery or soapy to the touch.