On Tue, 15 Aug 2017, Dave Horsfall <dave at horsfall.org> wrote:

>> On Mon, 14 Aug 2017, Paul Winalski wrote:
>> 
>> [ Ye olde 704 ]
>> 
>>>   TMP (transfer on plus)
>> 
> That's rather an odd mnemonic…

Actually, the 704 manual of operation gives the mnemonic as TPL:

http://www.bitsavers.org/pdf/ibm/704/24-6661-2_704_Manual_1955.pdf