\ 
194 
Quid sit pulchrtun, quid turpe, quid utile, quid non.— htor. 
Memoir on Vesical Calculi, and the Operation of Lithotomy ?Vi| 
Horses. By T. Girard, Director of the Royal Veterinary J 
School at A If or t: pp. 30. With plates , 1823. (Concluded.)* 
“ ALTHOUGH the same constituent principles enter into the composition 
of the calculi found.within the bladder of the horse and other monodactylesft 
still the stones themselves differ in many respects. They possess a unnoui 
odour which time slowly dissipates, but which exposure to the fire renews! 
and also a disagreeable flavour, partaking of that of the urine of the animal 
from which they have been extracted. In four horses and one ass we hav| 
met with the soft stones— of the consistence of paste, growing harder towarjM 
the centre; also becoming so by exposure to air, and at the same time lnabltl 
and easy of reduction to pow der. J 
“ Commonly these vesical concretions form petrifications, more or legl 
compact, mural, tuberous, or grained; of varied form and magnitude, po:,j 
sessing neither uniformity of colour, consistence, nor interior structure! 
they may lie either loose or encysted within the bladder. Generally, thetj 
have a yellowish tint, inclining to a white. Some are ovoid, otheis elongal 
ed and flattened; some, again, spheroid. Some are less compact in tlJ 
centre than towards the circumference; a smaller proportion possess ami 
cleus of some substance different from that of the stone itself. In soml 
the component material is confusedly heaped up together, without any dil 
coverable arrangement; in others, it is so amassed as to form distinct coM 
centric layers, w hose number is regulated by their thickness. 
“ Altogether, vesical calculi may be conveniently classed into four kinds | 
varieties? 1st, The soft species, whose consistence increases inwardly. 2j 
Those yellowish or whitish stones whose surface is asperous, or simply gran 
ed, and whose interior discovers an irregular amassment of saline mattei, mol 
or less coherent: these form the friable concretions which Lafosse alludes! 
when he directs us to crack the stone (if too large to be extracted) with tie 
forceps. The 3d kind includes those which display concentric layers, b* 
possess no nucleus. They are commonly grey, grained, and harder than ti 
precedin'*' kind. The 4th class is formed of those possessing nuclei; r 
which those composed of concentric layers exhibit a mural surface, ana 
hardness approaching to silex ; others, less compact, display a granulatl 
exterior, and are areolated within.” 
According to the results of the experiments of IVIessis. Fourci/ 
and Vauquelin, of which an account is contained in their elegat 
ii Dissertation on Vesical Calculi m Man and Animals in 
neral,” the stones found in the bladder of the horse are compos! 
of carbonate of lime, soluble with effervescence in the \\eak<t 
acids, whilst human bladder-stones yield products equally ij 
merous and diversified by combination. To this may be adde, 
in the ratio of about one-hundredth part, carbonate of magnesV 
) 
