Upvote:1
I thought I found the answer by chance, but I'm not convinced anymore. I was looking for all sorts of "corset", "stays" or "bodice", but this particular item might as well have been an "infant's binder" that is still in use today in a slightly different form.
Unfortunately, the Wikipedia article cites no sources for any of the claims about why these binders were used, including proper posture, preparation for corset wearing or to "lower the yell and squall from the baby by crushing its airways". The only claim that I could find (modern) evidence for is that the binder would keep the belly warm and thereby reduce the risk of colic.
Upvote:4
I think I will have to correct my earlier post. Both Grimm's dictionary and modern dictionaries make it quite clear that a Leibchen is a sleeveless upper garment* which can be used to suspend other garments (e.g. stockings) below. In fact, the "Good Sense" image in the OP shows examples of just that. One can think of it as the upper part of a dress. An example from the 1930s can be found here.
Another source that mentions Leibchens as a means to suspend other garments from can be found here (Brücke, Wie behütet man Leben und Gesundheit seiner Kinder, Wien 1892, p. 150, HT to @LangLangC):
Im frühen Kindesalter, wo die Geschlechter noch nicht unterschieden sind, haben die Schultern als Träger zu dienen, so dass die gesammte Kleidung mit Ausnahme von Stiefeln und Strümpfen an einem Leibchen aufgehängt ist, das mit seinen Achselstücken auf den Schultern aufruht. Nichts muss in dieser Zeit so fest um den Körper schliessen, dass es denselben irgend wie einengt.
In the early age of a child, when there is no difference between the sexes yet, the shoulders have to play the part of "carriers", so that the whole clothing except boots and stockings are suspended from a Leibchen, which rests on the shoulders. Nothing has to be so close fitting at that age that it restricts the body in any way.
The Grimms in one of their tales also mention a Leibchen in the context of keeping a child warm:
Und als es noch eine Weile gegangen war, kam wieder ein Kind und hatte kein Leibchen an und fror: da gab es ihm seins
And when she had gone a bit further, another child came and had no leibchen and was cold, so she gave him hers.
Here is part of an illustration of the same tale from the 1860s, the Leibchen is the darkish sleeveless outer garment on the upper body of the girl.
Looking at the scan of Der Bazar, it seems that the Leibchen mentioned there is really that thing in the middle of the scan, with two large holes for the arms and a band to close it around the breast. It frankly looks like it could neither keep a child warm nor have any positive effect on its posture. My uneducated guess would be that it is stiffened in order to deal with higher mechanical stress due to clothes being suspended below. Think about fastening trousers to a T-Shirt instead of using suspenders - the T-Shirt would probably tear quite quickly.
Original post:
The internet offers several simple options to sanity-check suspicious translations. One good choice is google image search (e.g. for "Baby Leibchen"), and another one is wikipedia. If you look at the German wikipedia article for Leibchen, the clothes depicted there look rather comfortable and practical. They also have links to somewhat historical Leibchens, but not older than mid-20th century. E.g. this one with stocking holders.
*Although it is sometimes used today (on the internet) for garments with sleeves