Possibly, he might have been a sort of incubating Watt or Brunel, who knows?
This chimney acts as a ventilator to the incubating chambers.
In two cases the male, and in two the female, was incubating.
An incubating female was collected as it departed from the nest.
But the missing testimony has not been supplied, though doubtless it is incubating.
"Gloom is there now ...