Time and again Emma creates her own dilemmas. The entire Eton fiasco is due to her meddling in matters she does not understand and ignoring clues that suggest she is on the wrong track because they did not fall into her plan. The only reason Emma has a dilemma with the Martin invitation is she can’t or refuses to see that Harriet by situation and sense would be lucky to have Mr. Martin for a husband and his congenial mother and sisters to teach and guide her.

Emma returns to the gate punctually so I think she, the driver or both have a watch. In an archived L&T post by JulieW she says women did wear watches and they were worn from a clip or equipage, see the link at the bottom of this message. I think the Martins were aware of the slight. JulieW made an excellent post on what would have offended the Martins by Harriet’s visit, see her post I think the Martin family on this board. I think the Martins reactions tell the story.

She had seen only Mrs. Martin and the two girls. They had received her doubtingly, if not coolly; and nothing beyond the merest common-place had been talked almost all the time… (Chapter 23)

Harriet is received doubtingly by the Martin ladies and they only speak of common place subjects rather than what had been the norm when Harriet stayed with them. I doubt they expected Harriet would be chaperoned by Emma and as JulieW said they would understand the snub of Emma not attempting to meet them.

-- till just at last, when Mrs. Martin's saying, all of a sudden, that she thought Miss Smith was grown, had brought on a more interesting subject, and a warmer manner…to be ready to return to the same good understanding; and they were just growing again like themselves…when the carriage re-appeared, and all was over. The style of the visit, and the shortness of it, were then felt to be decisive. (Chapter 23)

I think it is clear to the Martins that they are being slighted. The style of the visit, dropped off by Emma so her time is not her own and the prompt return of Emma and the summoning of Harriet leaves no doubt the visit was intended to be slightingly short.

The quarter of an hour brought her punctually to the white gate again; and Miss Smith receiving her summons, was with her without delay, and unattended by any alarming young man. (Chapter 23)

The “without delay” to me shows there is no hesitate, no drawn out farewell as there often is between friends.

She came solitarily down the gravel walk -- a Miss Martin just appearing at the door, and parting with her seemingly with ceremonious civility. (Chapter 23)

A Miss Martin comes to the front door with Harriet but exhibits only a ceremonious civility rather than the warm civility of a friend who has shared a home for six weeks. No one offers to walk Harriet to the gate—she is allowed a solitary walk back to her master—oh sorry, I mean Emma of course.

She had had many a hint from Mr. Knightley and some from her own heart, as to her deficiency -- but none were equal to counteract the persuasion of its being very disagreeable, -- a waste of time -- tiresome women -- and all the horror of being in danger of falling in with the second rate and third rate of Highbury, who were calling on them for ever, and therefore she seldom went near them. (Chapter 19)

Emma’s horror of the unworthy, the Martins and the Coles, treading in circles she believes is not meant for them is hypocritical and short sighted because she effectively does worse. Emma raised Harriet up in society based on her pretty looks and manners and her own fantasies and expected everyone to accept her, even going so far to believe a clergyman would take an illegitimate young woman to wife because she improved her. While Emma derides the Martins and Coles for their impertinence she expects her friends and family to receive the illegitimate daughter of somebody. I don’t have a problem with anyone who receives Harriet; I just think the contrast in what Emma expects from others and what she feels right in doing herself is a bit funny. Emma uses etiquette to deal out lessons to those she feels oversteps socially but the greatest offender to etiquette and the honest performance of duty in regards to visiting and connections is Emma. (;D)