This is as I suspected.  Unfortunately for me the Internet Archive Site 
has a pay wall.  I am allowed to see the title page of Andrews' 
article.  I remain curious as to the date of said entertainment.

On 1/20/23 10:58, Barbara Schmidt wrote:
> Scott,
>
> The DAY BY DAY entry is misleading.  The quote, found in Kenneth Andrews's
> NOOK FARM, is referring to an entry in Twichell's personal journal made on
> that date -- not a luncheon at the Hartford house on that date.
>
> Barb
>
> On Fri, Jan 20, 2023 at 12:40 PM Scott Holmes<[log in to unmask]>
> wrote:
>
>> I've come across an enigmatic entry in Day By Day for January 12, 1879
>>
>> January 12 Sunday – the Clemenses loved to entertain, something expected
>> of many Nook Farm residents. according to Twichell’s journal, a dinner
>> was given at Sam’s for Louis Fréchette, Poet Laureate of Canada:
>>
>> “M.T. /never was/ so funny as this time. The perfect art of a certain
>> kind of story telling will die with him. No one beside /can/ ever equal
>> him, I am sure” [Andrews 92].
>>
>> This doesn't make much sense to me as Twichell was not in Munich in 1879
>> and Sam was not at Nook Farm.  I believe the Andrews reference is to
>> Andrews, Kenneth R. /Nook Farm – Mark Twain’s Hartford Circle. /Seattle:
>> University of Washington Press, 1950.  I don't have access to that.
>>
>> --
>> /Unaffiliated Geographer and Twain aficionado/
>>
-- 
/Unaffiliated Geographer and Twain aficionado/