332 THE HORSE. 



Take of Spirit of Turpentine .... 2 ounces. 



Mucilage of Acacia .... 6 ounces. 



Gum Ammoniacura . . . . ounce. 



Laudanum 4 ounces. 



Water 2 quarts. 



Mix, and give half-a-pint as a drench every night : the bottle must be 

 well shaken before pouring out the dose. 



LARYNGITIS, ROARING, WHISTLING, &c. 



ONE OF THE MOST COMMON diseases among well-bred horses of 

 the present day, is the existence of some mechanical impediment 

 to the passage of the air into the lungs, causing the animal to 

 " make a noise." The exact nature of the sound has little or no 

 practical bearing on the cause that produces it ; that is to say, it 

 cannot be predicated that roaring is produced by laryngitis ; nor 

 that whistling is the result of a palsy of some particular muscle, 

 but undoubtedly it may safely be asserted that all lesions of the 

 larynx, by which the shape and area of its opening (rima glottidis) 

 are altered and diminished, are sure to have a prejudicial effect 

 upon the wind, and either to produce roaring, whistling, wheezing, 

 or trumpeting, but which would result it might be difficult to say, 

 although the precise condition of the larynx were known, which it 

 cannot be during life. Until recently veterinary surgeons were 

 puzzled by often finding on examination of a roarer's larynx after 

 death no visible organic change in the opening, and many were led 

 to imagine that this part could not be the seat of the disease. On 

 a careful dissection, however, it is found that a muscle or muscles 

 whose office it is to dilate the larynx is wasted and flabby (crico- 

 arytenoideus lateralis and thyro-arytenoideus). The other muscles 

 are perhaps equally atrophied, but as their office is to close the 

 opening, their defects are not equally injurious, and at all events 

 are not shown by producing an unnatural noise. The cause of this 

 wasting is to be looked for in pressure upon the nerve which sup- 

 plies these muscles, and which passes through an opening in the 

 posterior ala of the thyroid cartilage, so that whatever causes a dis- 

 placement of that part will mechanically affect the nerve. For 

 these several reasons it will be necessary to examine first of all into 

 the several kinds of inflammation, &c., to which the larynx is sub- 

 ject, and then to investigate as far as we may, the nature, mode 

 of detection, and treatment of the several conditions known to 

 horsemen by the names of roaring, whistling, &c., which are only 

 symptoms of one or other of the diseases to which allusion will 

 presently be made. 



BY ACUTE LARYNGITIS is meant a more than ordinary inflam- 

 mation of the larynx, and not that slightly morbid condition in 

 which the mucous membrane of that organ is always involved in 

 " the passage of a cold into the chest." In the latter state the ear 



