HYDROTHORAX. 107 



following, once every second day, for a week, with fric- 

 tion or rubbing: — Oil of turpentine; oil of olives; equal 

 parts mix. This is a simple, cheap, and good liniment, 

 and will answer every good purpose. For diseases of 

 the hock joint, see Spavin. 



Hooks in the Eyes. — This is a term in use by 

 country folks when referring to the peculiar action of 

 the memhrana nictatans in cases of locked-jaw, (which 

 see.) Many persons have advised that these useful 

 membranes should be cut out. Nothing could be fur- 

 ther wrong than this ; for it is merely the effect of a 

 cause. Rather remove the cause, or cure the locked-jaw, 

 and the protruding of the hook or horns will cease. This 

 is the only true plan to adopt. 



Horse, Natural History of the. The horse 



comes under the division vertebrata, class mammalia, 

 tribe Ungulata, order Pachydermata, family Solipeda. 



Horse Fly. — This comprehends the gad or breeze 

 fly, GasteropMlus oestrus. The spotted horse fly, Gr. 

 Equi. The red-tailed horse fly, (7. heinorrlwidalis. 

 This last fly deposits her eggs on the lips of the horse, 

 and the former glues them to the hair of the legs. 

 These various eggs are ultimately taken into the sto- 

 mach, and in one year they have become sufiiciently 

 matured that they are thrown out to the outer world to 

 get wings, an^ finally fly about and propagate their kind 

 in the same manner as the parent stock. (See Worms.) 



Hydrothorax. — This is a name given to water when 

 it accumulates in the chest. Hence, hydro, water, and 

 thorax, the chest. 



Causes. — Debility from the effects of inflammation of 

 some of the organs within the chest. 



