The electric and magnetic field applets use every possible combination of mouse buttons and modifier keys (these are sometimes called chords) to do interesting things. There are too many of them to list in each module, so the complete list is here for easy reference. You may want to open this page in another browser window in order to keep it visible. But after a while, using the chords will come to seem as natural as falling off a bicycle or using Emacs.

Not all of these chords will work in every instance of a field applet. Sometimes capabilities are disabled because they are inappropriate or even incorrect for a lesson or a particular field. You shouldn't worry about this.

How many buttons have you got?

You must realize that not all mice have the same number of buttons. The table below assumes that you have a three-button mouse, as is found on most Unix workstations. If you are using a PC, you should have a two-button mouse. In that case, to simulate the middle button, you should use the left button while holding down the ALT key. If you are using a Macintosh, you should have a one-button mouse. In that case, the single button corresponds to the "left button" in the table. To simulate the middle button, use the single button while holding down the ALT (OPTION) key, and to simulate the right button, use the single button while holding down the COMMAND (clover) key. To summarize:

Mouse Buttons

Unix

Left
Middle
Right

PC

Left
Alt-Left
Right

Mac

Button
Option-Button
Clover-Button

On a Unix workstation, you can, if you want, use Alt-Left in place of Middle, and Meta-Left in place of Right. On all three types of machines, you can, by judiciously combining modifier keys and mouse buttons, make the program think you have simultaneously pressed both the right and middle buttons. The program will then perform both actions.

Play those funky mouse chords

A chord consists of a mouse button and possibly either or both of the shift and control keys. There are therefore twelve distinct chords. Since the mouse buttons may be simulated with other modifier keys, you could be using three or four (for a Right+Middle double chord) modifiers at a time. It's actually kind of fun.