Ok, I'm a day late. That old book is hard to read.
I got out a 1971 rule book and took a look.
The rules were way more disorganized back then. There were 41 rules in those days. They have been reorganized and ordered to the 34 we have today.
The biggest change I can say I saw was that there was no concept of a Substituted Ball back then. No real difference in Match Play, but pretty big in Stroke play.
If you accidentally switched balls while yours was lifted, you had to correct it before teeing off on the next hole. If not you were DQ'ed same as a Wrong Ball. If you didn't have the old ball, you were out of luck. This was changed around 1980 when an LPGA player tossed her ball to her caddie who missed it and it went into a hazard where it couldn't be recovered. She was DQ'ed. Now she would get two strokes for substituting when not allowed.
Lots of other rules have had penalties changed. For example, teeing off outside the teeing ground is now 2 strokes and must be corrected. In those days there was no penalty, but you had to correct it and all the strokes played counted.
If you lost your ball in ground under repair you got relief similar to today, but if you lost your ball in an obstruction you were out of luck.
There was no definition of Line of Putt although the term was used and the definition of Lost Ball was simpler, but the definitions were pretty similar otherwise.
In general, I'd say the rules were slightly less complicated than today, but had some gaping holes in them and were much more disorganized.