To set the number of images per line, a new class can be created that contains a clear:left; This class can be applied to any element where the line break is needed. Don't forget, you can specify more than one class within a class attribute:
<div class="pic newLine">
<img src="images/cloud4.jpg" width="100" height="75" alt="cloud" />
<p>Cloud Four</p>
</div>

Cloud One

Cloud Two

Cloud Three

Cloud Four

Cloud Five

Cloud Six

Cloud Seven

Cloud Eight

Cloud Nine

Cloud Ten

Cloud Eleven

Cloud Twelve