As advised by Mrs Beeton in the 1880 edition of her Household Management:
The Sleeping Baby – and the nefarious practices of unprincipled nurses
We have two reasons – both strong ones – for urging on mothers the imperative necessity of early making themselves acquainted with the nature and wants of their child: the first, that when left to the entire responsibility of the baby after the departure of the nurse she may be able to undertake her new duties with more confidence than if left to her own resources and mother’s instinct, without a clue to guide her through the mysteries of those calls that vibrate through every nerve of her nature; and secondly, that she may be able to guard her child from the nefarious practices of unprincipled nurses who, calming the mother’s mind with false statements as to the character of the baby’s cries, rather than lose their rest or devote that time which would remove the cause of suffering, administer behind the curtains those deadly narcotics which, while stupefying Nature into sleep, insure for herself a night of many unbroken hours…
We must strenuously warn all mothers on no account to allow the nurse to sleep with the baby, never herself to lie down with it by her side for a night’s rest, never to let it sleep in the parent’s bed, and on no account keep it longer than absolutely necessary confined in an atmosphere loaded with the breath of many adults.
The amount of oxygen required by an infant is so large, and the quantity consumed by mid-life and age, and the proportion of carbonic acid thrown off from both so considerable, that an infant breathing the same air cannot possibly carry on its healthy existence while deriving its vitality from so corrupted a medium. This objection, always in force, is still more objectionable at night-time, when doors and windows are closed, and amounts to a condition of poison when placed between two adults in sleep and shut in by bed-curtains.; and when, in addition to the impurities expired from the lungs we remember, in quiescence and sleep, how large a proportion of mephitic gas is given off from the skin.
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