In fact, it is very likely that in reality the car was Hum's big Nash. (That being so, Enid must have sat on someone else's knee - probably Jack Scott's, just as "Gladys" sits on Jack Callcott's knee later at Mosman Bay.)

As mentioned above, Hum was unlikely to have driven the Lawrences back to town after the tea-party at Narrabeen, because he and his family were almost certainly staying at their holiday house in Collaroy Basin - in Seaview Parade, in fact (where Hum's son told John Ruffels they regularly holidayed in the school vacations).

If that is so, then the Hum family must have been first "dropped off" in Seaview Parade, before Lawrence and Frieda were driven (by someone else) back to town.

That would imply that they switched cars at The Basin - from Hum's Nash probably to the Friend-family Austin (usually garaged at Taylor's Garage in town).

That in turn would imply that they walked from Seaview Parade to the Friend holiday place in Beach Road (cf. Yeend's advice that "I would be better off looking in Beach Road", cited above), where, presumably, the Friends' Austin was then parked.

Now, I know from my more than 10 years living in The Basin - one block away from Seaview Parade - that there is a beachside track leading from Seaview Parade to Beach Road.

It runs past "Hinemoa", and is in fact the quickest and most direct way to get from Seaview Parade to Beach Road.

(I used to walk down it almost every day to get my newspapers from a newsagent in Pittwater Road, Collaroy - though little did I realise I was traversing the same path that Lawrence had taken on Sunday afternoon, May 28, 1922.)

At last the ill-fitting parts of the jigsaw were beginning to come together.

The strong likelihood is that one of the other passengers in the car from Narrabeen was Jack Scott.

Firstly, the text says that Callcott (aka Jack Scott) was in the car - and the presumption must initially be in favour of what Lawrence says in the text.

The text goes on to say:

I now believe that this was a combination - an amalgam if you like - of Scott being "put down" at his flat at 112 Wycombe Road, Neutral Bay, after the Hums had been "dropped off" earlier at Collaroy Basin.