Transvaal Postal History Help

I have a cover that's a bit ... complex. I'd like some help in deciphering it. I don't think it's Boer war related, but was certainly sent during that era. It looks to me like it was mailed from Johannesburg on November 12, 1901, registered with Mashed Persia as the destination, likely a misspelling of Mashad. When it arrived it was forwarded to London, and seems to have had a bit of a life during the whole process. It looks like it didn't arrive until sometime in February 1902, yet has a London marking from December 1901, perhaps misrouted to Baku where it received the January 29 marking?

What a fascinating assortment of stamps and postmarks!

I can't help you with any of them, but I can decipher the handwriting, if that helps.

Registered
Mrs Temple
care of His Britannic Majesty's Consulate General
Mashed [sic]
Persia

redirected to:

care of Lady Temple
Heathbrow (?), Hampstead, London

Yeah, I was able to puzzle that out, though had issues with the Heathbrow part. I haven't googled to find out if that name is correct or not, I know addresses in the UK seem a bit weird to those of us who are used to street number instead of building names. I see a Teheran, a Tabriz and a Meshed receiver on the back. I can't tell for sure what the dates are for each though, except that the Teheran seems to be dated in 02. What seems weird is the Dec 1901 registered mark from London, then later a February 1902 registered mark, also from London. My current guess is it went to Meshed where it languished for some time, then sent to London where it was mis-sent back (which might explain the Baku(?), Cyrillic anyway) marking, before going back to London where it was correctly routed to the destination. The Arabic marking on the front to the left of the registry number might give a hint, the purple Arabic number at center right do match '495', so a duplicate of the registry number. I wonder about the possibility it didn't have enough postage on it for the forwarding, so was sent back to the origin and those two stamps at left were added to pay for that service. Note that they have a different cancel than the two stamps at upper right. I can't quite make out a date on those...

Heath Brow's mentioned in Hansard, 2 November 1932- "The building is to be used as a town headquarters and officers' mess for No. 604 County of Middlesex Auxiliary Air Force Squadron".

Hansard's the published record of Parliament. Otherwise, the name seems to be now attached to a "rather expensive car park" for visitors to Hampstead Heath.

Drew a partial blank on the promotion of Mrs Temple to Lady Temple. There appears to have been a society marriage about this time which eventually produced a Lady Mount Temple, but I don't think this is the one.

Heath Brow was built for Sir Richard Temple in 1890, and was destroyed by a land mine in 1941. The addressee could be Miss Temple.

edit: Naval mine attached to a parachute and dropped by an aeroplane. Maybe the Luftwaffe was aiming for the Thames.

As well as Mount Temple, they also had a (Richard) Carnac Temple.

I don't think it was Miss Temple. Mrs Temple seems clear enough for me. Thus, the address would be:

Mrs Temple
c/o Lady Temple
etc.

There were a number of male children and siblings of Sir Richard Temple, and presumably about the same number of Mrs Temples, many of whom were involve in Colonial diplomacy and military. So it would be quite natural for a Mrs Temple to stay, or at least an extended visit, at the old pile while hubby does his globetrotting.

Also of possible interest is that Sir Richard Temple dies in March 1902. While the death is generally reported as sudden, it possible that this letter was in response to bad news from home.

Yes, didn't think of that! Slaps forehead.

Mrs. Temple was the daughter-in-law of Lady Temple, and staying there during the latter portion of the Boer war. Sir Richard Temple died from a heart attack at his residence in Hampstead according to my search, and Lady Temple would have been his wife. Not surprising that there isn't an enclosure, which would have made it much easier to figure out, or not as the case may be.

The originating cancels are pretty obviously Johannesburg, November 12 1901 and is repeated on the back such that it overlaps the flap, as required for registered mail. Note that the letter was originally underpaid with the two 2 1/2d stamps, so the sender was redirected from the clerk (#10) to the Registered letter clerk (#9) who added the other two stamps for them, overpaying the rate by 1/2d. The second cancel is that November 13 1901, but I can't make out the city, probably Durban. I'm guessing the third cancel to be applied was the London Registered, applied in early December (6?, 8?, 9?) 1901. It then would have taken the northern route to Persia, RR through Russia to Baku before floating over to match the Tabriz transit stamp. From there to Teheran then Meshed where it was discovered that Mrs. Temple no longer resided at the consulate. At Meshed it was marked Retour and the Arabic inscriptions 'London' and '495' were added and it retraced the route back to London, arriving on February 18 1902. It then went to the London N.W. office the next day, and was immediately sent to the Hamstead N.W. office the same day for delivery.
The recipient was Florence Elizabeth Temple (nee Karslake) the wife of Colonel H.M. Temple (younger son if Sir Richard Temple), who was the Consul-General in Meshed. I don't yet know if Colonel Temple was still in Meshed when the letter arrived, but we know his wife had moved back to England by late December.
Now, I need to condense all that to fit on a page so I can keep it together with the cover. I'm at three pages with my Word doc, so it will either be really tiny text or I will remove some of the detail. :)

The second stop is definitely Durban, Natal. I wonder if there is a censor mark under Baku, to the right of Durban?

Here is a reference to Lt-Col Temple at Meshed in 1901-02, from the 1905 Consulate reports held in the Qatar Digital Library: