144 
THE AIR-SYPHON VENTILATOR. 
THE AIR-SYPHON VENTILATOR. 
This new mode of ventilation, a notice of 
which is to be found at p. Ill, of the current 
volume, was patented by Dr. Chowne, of Eng- 
land, and is based on the principle that, "If a 
bent tube or hollow passage be fixed with the 
legs upwards, the legs being of unequal lengths, 
whether it be in the open air or with, the shorter 
leg communicating with a room or other place, 
that the air circulates up the longer leg, and 
that it enters and moves down the shorter leg ; 
and that this action is not prevented by- making 
the shorter leg hot, whilst the larger leg remains 
cold ; and no artificial heat is necessary to the 
longer leg of the air syphon, to cause this action 
to take place." Thus, by using the chimney of 
an ordinary room, for instance, (into which air 
has free access,) as the longer leg and by con- 
ducting a tube or channel constituting the short 
leg of the air syphon, from any part, (as near 
the ceiling, for instance,) into the lower part of 
the chimney, at the suitable place, a current of 
air will proceed from the apartment down the 
shorter leg, and away up the longer one. 
Air-Syphon Ventilator. — Fig. 45. 
The means of ventilation can be conducted by 
light lead or zinc tubes, passing round and 
through a room, and finally into the fireplace ; 
and tubes passing from these to the upper parts 
of the room, the warm air would consxantly de- 
scend through them to the continuous channel, 
and then into the longer leg of the syphon. 
In the above illustration, the dotted lines, a, 
and b, represent pipes about two inches in diam- 
eter, which are concealed behind the upper part 
of the jambs, and communicate with the chim- 
ney opening, thus forming an inverted syphon, 
the flue of the chimney being the longer leg. 
To draw off" the gases or air from the middle 
portions of the room, a pipe may be conducted 
from the bottom of an ornamental vase a, into 
the flue, when the air would take the course 
as shown by the arrows ; and to remove the 
air from the upper portions of the room, another 
concealed pipe may communicate with a small 
aperture above the jamb, as at b, thereby 
immediately establishing thorough ventilation. 
A peculiar fact is, that this mode of ventilation 
affords facilities hitherto not known for carrying 
away the heat, and other products of combus- 
tion from gas burners, and other lamps, of which 
the products are offensive. Again, wherever 
the air-syphon ventilator is in operation, it is 
certain, that, should an accidental escape. of gas 
take place, it will not accumulate, but descend 
from the upper part of the room, by means of 
the shorter leg of the syphon. This apparatus 
admits also, of being extemporaneously and 
temporarily set up in a sick room, so as to cause 
a constant removal of air from the upper portion 
of the apartment, where it is so apt to hang 
about the curtain furniture of the chamber, and 
to impregnate it with the exhalations which are 
so often the result and generators of disease. 
In a similar manner, the air syphon can be 
applied to the ventilation of churches, school 
houses, barns, conservatories, wells, cellars, 
vaults, &c, &c, In short, if what is said of it 
be true, it is one of the greatest discoveries of 
the age. 
DISCOVERY OP THE CAUSE OF THE YELLOWS IN 
THE PEACH TREE. 
Although the various journals devoted to ag- 
riculture throughout our broad land have teemed 
with articles on the disease called " the yellows 
of the peach tree," I believe a small beetle, 
named in Harris' Catalogue, Tormicus liminaris, 
has never, until lately, been suspected as the 
cause of that destructive malady. 
I will not presume to say that it is the sole 
cause of the decline of the peach tree, for I am 
aware that unhealthy soil, late and hard frosts, 
the large borer, (^Egeria,) and too profuse bear- 
ing, will ail injure the trees and cause death ; 
but I believe the little tormicus will be found to 
produce that disease which is believed by many 
to be infectious. 
Though the Tormicus liminaris, in its perfect 
state, has long been known to science, its habits 
in the grub or larva form are little known, and 
few have been led to search for them in the bark 
of the peach tree, where they may be found in 
incredible numbers. They are so minute, that 
only a close observer would see them ; but like 
the itch mite in the human family, they produce 
disease, and frequently death. 
When the peach tree is infested with the Tor- 
micus liminaris in sufficient numbers to cause 
disease, the tree will throw out great numbers 
of sickly shoots, in August and September, at 
which time the grubs may be found securely feed- 
ing in the sap vessels of the inner bark of the 
tree, effectually protected from all external inju- 
ry by the hard outer bark. Too minute to at- 
tract attention, these little creatures do their 
work secretly and surely, uninjured by any of 
