Capacitance Meter diagram question

[Gualdhar]

Sorry for a possibly newbie question, but I'm trying to build the Capacitance Meter listed at http://www.electronics-lab.com/projects/test/006/index.html and I'm wondering about the symbol for the 47k, 470, and one of the 10k resistors.  It has a resistor with something that looks like maybe a feedback loop? I can't tell what it is or how to build it, and could use some assistance.

Thanks in advance.

 

[Hero999]

They're potentiometers (variable resistors) which are used to calibrate the meter.

 

[Alex Tsekenis]

Adding on Hero's post, they look like this:

The second type is probably what you are looking for for your capacitance meter.

You can buy them very cheaply at your local electronics shop.