This Night Ride show was for 2 hours, the first hour presented by Peel and the second by Robin Boyle. Looking at the PasB, it does not say which part of the show Peel finished and Boyle started. Therefore I'm guessing that the Raag Kirwani was the last song on Peel's section before Woody Herman's The Magpie track, which doesn't seem to be a record that he would play. Like most non-Peel Night Rides, Boyle's playlist is mainly easy listening music and jazz.
BBC Genome  describes the show as "John Peel exploring the world of words and music in his own special way and Robin Boyle with the usual Night Ride". The producer is Denis O'Keeffe.
Robin Boyle (obituary here ) didn't have much in common with Peel; he was one of the older generation of BBC Light Programme presenters, and had a long career as the popular host of Radio 2's Friday Night Is Music Night.
Peel interviews someone called Lady Diana Dukes about meditation. This may well have been the widow of Sir Paul Dukes (1889-1967), author and intelligence officer, whose works include a number of books on yoga, written in the 1950s.
Peel plays an electronic track from Morton Subotnick. According to Wikipedia, it was the first piece of electronic music commissioned by a record company, the company in question being Elektra's classical music subsidiary Nonesuch - which may explain why it came to Peel's attention.
This seems to be one of the few Night Ride shows with no guest poet - neither this tracklisting nor Ken Garner's The Peel Sessions mentions one.
Peel continues talking to Lady Diana Dukes about meditation
North Indian Classical Music: Raag Kirwani - Surbahar Solo (BBC Archives)
↑The PasB may be wrong here. A version of William Byrd's "The Earle of Salisbury" appeared on the "live" half of Pentangle's double LP, Sweet Child, in late 1968, but the version played on this show is likely to be the opening track from John Renbourn's LP Sir John Alot of Merrie Englandes Musyk Thyng and ye Grene Knyghte (Transatlantic), issued in spring 1968 and a Peel favourite at the time