Script For Switching Between Two Applets

I have 2 web cameras that are displayed in my html page by two different
applets. I did not write the appletts, I just put them into the web page.

Question 1: Is there a way to have this image on the page change from one
camera to the other every 15 seconds?
Question 2: Is there a way to have the cameras only appear during a certain
time of the day and have a jpg appear the rest of the time - i.e. daylight
hours?

Camera #1
(I altered the actual link to the cameras.)

<applet name="cvcs" codebase="http://x.x.x.x:80/" code="xplug.class"
width=320 height=240</td>
<param name="RemotePort" value="80">
<param name="Timeout" value=5000>
<param name="RotateAngle" value=0>
<Param name="PreviewFrameRate" value=2>
<param name="DeviceserialNo" value="aGFyYm9yOm1hcmsxMjM=">
</applet>

Camera #2

<applet name="cvcs" codebase="http://x.x.x.x:81/" code="xplug.class"
width=320 height=240</td>
<param name="RemotePort" value="81">
<param name="Timeout" value=5000>
<param name="RotateAngle" value=0>
<Param name="PreviewFrameRate" value=2>
<param name="DeviceserialNo" value="aGFyYm9yMjptYXJrMTIz=">
</applet>