Cold feet in church?

These drawings were taken from a 1931 Dutch Roman Catholic magazine reporting on an efficient heating installation for church goers.
The author of the article complains about how much cold he has suffered in Roman Catholic churches for want of proper heating.

Even priests in the pulpit, for as long as three quarters of an hour at temperatures somewhere around freezing point, can have their own made to measure pulpit-heating. This was sold by Siemens-Schukert in The Hague.

To this day no research has been done on how many of these were actually sold and how much of these remain in churches up to this day.
A lot of them have ignorantly been removed during restauration campaigns or for conservation purposes. Alas it is still not recognized that electrical installations (among other 'modern' comforts) are also very much part of the church interior and its history. It has every right to be studied, conserved and researched, just like -say- a 17th century devotional statue.
I intend to do my small bit of awareness raising through my paper on electrical lighting in churches.