VENTILATION 



1596 



VENTRICULUS 



about either by extracting the foul air from the room, 

 or by forcing pure air into the room, and is effected 

 by means of fans, heat, gas, or steam. A T atural 

 ventilation is aided by means of tubes or shafts 

 employed as inlets and outlets. The outlets are 

 guarded by Cowls, which prevent the entrance of rain, 

 increase the extracting effect of the wind, and check 

 the tendency to down-draught. A most valuable agent 

 in this ventilation is the chimney. Windows also may 

 be utilized for the same purpose. The estimation of 

 C0 2 in the air may be made by the following methods : 

 I. Minimetric Method, when the proportion of C0 2 is 

 not less than one part per iooo. The analysis is made 

 by the use of a solution of sodium carbonate with phe- 

 nolphthalein as an indicator. 2. Pettenkofer ' s Method 

 has for its basis the fact that if air containing C0 2 

 is brought into contact with barium hydroxid in solution 

 a combination takes place between the barium and 

 C0. 2 immediately, and insoluble barium carbonate 

 is precipitated. 5. Szydlowski's Method consists in 

 comparing a given volume of the air to be tested with 

 a sample of air from which C0 2 has been removed, 

 and the difference of pressure recorded by means of 

 a mercurial column. 4. Reiset's Method, calculates 

 the amount of CO, 2 in the air from the difference 

 found between the titration of a given volume of 

 barium- water before and after the passage of the air 

 through it. V., Methods of; there are various methods 

 of securing ventilation, some of which are as follows: 

 Auburn or Pentonville System of ventilating prisons. 

 The cells are arranged in blocks of several tiers in 

 height, and each block is surrounded by an outer build- 

 ing, between the walls of which and the doors of the 

 tiers of cells on each side is an open corridor, not 

 divided by floors corresponding to the floors of the 

 several tiers. The air is drawn from this corridor into 

 the cells. Boyle' 1 s Ventilator, an arrangement of mica 

 valves allowing air to pass out, but allowing no back- 

 draught. Cooper's Ventilator , a series of apertures in 

 the glass of a window-pane arranged in a circle so as 

 to be more or less completely closed by a circular disc 

 having corresponding apertures and moving upon a 

 central pivot. Ellison'' s Ventilating Bricks, are bricks 

 perforated with conical holes, and fixed in the walls, 

 with the apices of the cone on the outside. They are not 

 likelv to produce a draught. Hinckes- Bird's Method 

 consists in placing a movable block of wood under the 

 entire length of the lower window-sash. Louvred Panes, 

 a form of window-ventilation by which an upward di- 

 rection is imparted to the incoming air. These panes 

 take the place of one or more of the squares of glass, 

 and may be either opened or closed. Mc Kinnelf s Ven- 

 tilator, a combined outlet and inlet ventilator, which is 

 applicable in the case of upper rooms or rooms in single- 

 story houses. It consists of two tubes, the one encir- 

 cling the other, the inneractingas the outlet, and being 

 fitted with a cowl. Sheringham Valve, a common 

 form of inlet in windows or walls for the purposes of 

 ventilation. The entrance to the opening in the wall 

 is guarded by a strainer to keep out dust, while on the 

 inside is a valved iron plate with closed sides and 

 hinged at the bottom. This opening is usually placed 

 near the ceiling. Smfad-Dowd System of Ventilation, 

 an artificial system of ventilation in which the outlets 

 are at the bottom of the sheeting along the floor-line 

 and open into spaces beneath the floor. These spaces 

 are connected with (lues down which the air is drawn 

 by the powerful action of the furnace-chimney. '1'obiri ' s 

 Tube, a means of ventilation, the air from without enter- 

 ing through a hole in the wall and being conducted 

 by an upright tube into the upper portion of the room. 

 V., Pulmonary, the supply of pure air to the lungs 



and the removal of the vitiated air. V., Respiratory, 

 the supply of a fluid containing oxygen to a respira- 

 tory membrane and its removal after the oxygen has 

 been given up. 



Ventilator (ven f -til-a-tor) [ventilare, to fan]. An ap- 

 paratus for effecting ventilation. 



Ventrad (ven' -trad) [venter, stomach; ad, toward]. 

 Toward the ventral aspect or surface ; not dorsad nor 

 neurad, and not laterad. 



Ventral (ven'-tral) [yentralis ; venter, belly, or abdom- 

 inal cavity]. Pertaining to the belly. At or in the 

 direction of the venter or belly-side of the body or the 

 ventral aspect of an organ. Uemal is sometimes 

 instead of ventral. See the opposite, Dorsal ; also, 

 Position and Direction, Table of Intrinsic Terms. 



Ventrally (ven' -tral-e) . Synonym of Ventrad. 



Ventricle (ven'-trik-l) \yentriculus : dim. of venter, a 

 belly]. Applied to certain structures or parts having 

 a bellied appearance. V., Aortic, the left ventricle 

 of the heart. V. of Arantius, a cul-de-sac in the 

 oblongata. Vs. of Brain, the third, fourth, fifth, and 

 two lateral. V, Third, between the optic thalami and 

 extending to the base of the brain; V, Fourth, the 

 space between the oblongata and pons in front, and 

 the cerebellum behind ; V, Fifth, the cavity between 

 the laminae of the septum lucidum; V, Lateral, the 

 considerable cavity of either half of the cerebrum, 

 communicating with the third through the foramen of 

 Monro. Each ventricle consists of a triangular central 

 cavity or body, and three smaller cavities, called cornua. 

 The corpus callosum forms the roof of the body, the 

 septum lucidum the mesal boundary, and the floor is 

 formed by the corpus striatum, taenia semicircularis, 

 optic thalamus, choroid plexus, corpus fimbriatum, and 

 fornix. The anterior cornu curves forward and out- 

 ward into the anterior lobe of the brain, the middle 

 cornu descends into the middle lobe, and the posterior 

 cornu or digital cavity curves backward into the occipi- 

 tal lobe. V. of Cerebellum, the extension of the 

 fourth ventricle into the substance of the cerebellum. 

 V. of Cord. See Canal, Central. V. of Corpus 

 callosum, the space between the labium cerebri and 

 the callosum ; the callosal fissure. V. of Larynx, a de- 

 pression between the true and false vocal bands. V., 

 Left, of Heart, that upon the dorsal and left side of 

 the heart, and which, through the aorta, forces the 

 blood over the general system. V. of Morgagni. 

 a small cavity bounding each vocal band externally. 

 V., Optic, the cavity of either optic or geminal lube. 

 V., Right, of Heart, that forcing the blood through 

 the pulmonary artery toward the lungs. V., Sixth 

 Verga's V., and Canal, Central. V., Sylvian. Same 

 as V, Fifth. V., Verga's, a space occasionally found 

 between the callosum and the fornix. 



Ventricornu (ven-trik-or 1 '-mi) [renter, venter ; 



cornu]. The ventral extension, or anterior horn, of 

 the gray matter of the myelon. 



Ventricornual (ren - trik - or'- nu - al) [renter, venter; 

 cornu, cornu]. • Pertaining to the ventricornu. 



Ventricose (ren'-trik-oz) [renter, abdomen]. Intlated 

 or swelled out on one side, resembling an abdomen. 



Ventricous (ren'trik-us) [renter, belly]. In l>ii 

 distended, resembling an abdomen. 



Ventricular (ren trik' -u-!ar) [reiitricultis, a vein ride]. 

 Belonging or pertaining to a ventricle. V. Aqueduct. 

 See Aqueductits Svlrii. V. Bands, the longitudinal 

 folds of mucous membrane above and parallel to tin 

 vocal bands. The false vocal bands. 



Ventriculose (ven - trik'- u - loz) [reutriculus, 1 

 Minutely ventricose. 



Ventriculous (ven-trik'ti-lus). Same as Ventricular* 



Ventriculus (ren-trik' -11-liis). See Ventricle. 



