The three uses are:

i. as the article suggests, dance card pencils -or-
ii. bridge pencils used for scoring in the card game bridge.
iii. Spine housed diary/address book pencil

Spine housed pencils in address books would be of a similar diameter but substantially shorter (maybe 6cm in length to fit easily into a small address book). These pencils seem too long for a pocket diary pencil.

Looking at the pencils, I would say that the pencils with the metal loop in the end are more likely to be dance card pencils (typcally held on a chain around the neck of the lady) and probably post-WWII. Prior to WWII it was more common to house the pencil in a SILVER pencil holder/extender which was more decorate.

The other pencils with the more usual ends could be either bridge or dance card pencils.

1920s onwards: Often dance cards would be placed into a dance card holder (owned by yourself). This holder would often be a small leather wallet type case with either a space in the spine

Bridge pencils would hardly ever be marked with the manufacturer as this would be more prominently displayed on the case (either leather or in a cardboard box). They are typically 8-10cm long and are always circular in cross section. Oddly enough they are always sold in sets of four, but despite bridge being a four player game, only two would be used at once … one person from each partnership would record the score. Typically the set of pencils would eb provided by the host.

A similar game whist does not have fixed partnerships and typically each player would bring his/her own pencil to record scores as players would each move in different directions around the hall. As you needed your own pencil or pen you would not buy a set of the relatively expensive bridge pencils as a regular pencil would suffice and cost a fraction of the bridge set.

If I had to label the two without loops, I would probably mark them as bridge pencils. As they attracted a premium price (I recall a set of 4 costing £8 for nice looking set in a cardboard display case in the 1990s) as usually were tipped in metal until recent years to try and justify the premium.

Ihre Website, auf der ich mich schon einige Male mit Freude umgesehen habe, ist sehr interessant! Danke für die Mühe, die Sie sich damit machen.

Stimmt, diese Verbreiterung an der sog. Tellerkapsel soll das Herausrutschen verhindern (hier gibt es zwei Exemplare mit einer solchen Kapsel zu sehen, darunter auch einen mit dem Namen „Memorandum”).

Von welchem Hersteller stammt denn der „Flag-Pencil”?