Thank you all for your responses. I plan to stock up on Ivory and rotate my stock just as I do now.
Not being very adventurous I have not tried many soaps but I was attracted to Neutrogena facial soap which is made with our friend glycerin. It is a clear amber bar, quite pricy, ($2.50/3oz bar), but goes a long way, (pun intended), in enemas. The soap is POWERFUL!
Not irritating or burning but it stimulates the colon very rapidly producing a complete evacuation of the lower bowel.
Neutrogena is a waxy soft soap but does not dissolve rapidly in water, which for me was a good thing. I cut off a chunk about 1/6th of the bar and worked hard to get it to dissolve in warm water. Once the water was cloudy I stopped trying to dissolve the stuff and put the remainder away with the bar. Approximately 1/2 of the chunk had dissolved and I added to that enough warm water to make two quarts.
I put it in my bag and took it laying on my back on a bathmat in the bathroom, (a lucky choice). When about 1/4th of the water was in I noticed an urge, not too strong but quite noticeable. By the time the first quart was in I was having strong cramps requiring clamping off the flow until the cramps passed. I did manage to get the whole bag in with several pauses for cramps but retention was impossible.
Using the laying on back position allowed the solution to get to the transverse colon and when I began to evacuate with strong movements. I certainly felt cleaned out when most of the water was out but still had the feeling that more was coming so I hung out in the house and in about 30 minutes a sudden urge sent me back to the toilet. A very large amount of dirty water squirted out in a single stream followed by several smaller bursts.
Within an hour of the first expulsion I was empty and very well cleaned out. The effect from the very beginning was a very powerful urge to evacuate building up rapidly to a "can't hold it" point. A very good enema.