MISCELLANEA. 
53 
ing is advantageous. This animal has only one stomach, 
which somewhat resembles that of man, and accordingly it 
is advantageous to prepare the food and so assist the diges- 
tive organs. Besides which, boiled roots are more palatable 
to the animal, and will be partaken to a much larger extent, 
than if raw, so that the pig may be partially fatted on them, 
and much meal saved. And as roots are cheaper than meal 
in proportion to the nourishment contained, there is a decided 
advantage in using them in combination. It is unnecessary, 
however, to boil roots for store pigs. Although boiled roots 
have not been found advantageous for fatting cattle, yet 
when milk is the object they have been found to answer the 
purpose of the cowkeeper, and to produce a larger quantity 
of this secretion. — Prize Essay by IF. C. Spooner. 
ON THE QU ANTITY OF SULPHATE OF ATROPINE REQUISITE 
FOR THE DILATATION OF THE PUPIL. 
Amongst the narcotics which induce dilatation of the 
pupil, belladonna occupies the first place. Its best prepa- 
ration is the sulphate of atropine, which in weak solution 
has no irritant effect, and is free from that mechanical action 
which may be objected to the extract of belladonna, while 
through its uniform composition, it can be applied in pre- 
cisely regulated strength. 
The English w T ere the first to introduce this preparation 
into practice. In London it is generally used in the proportion 
of 4 grs. of sulphate of atropine, to an ounce of distilled w 7 ater. 
A single drop of this, retained in contact with the cornea and 
conjunctiva for only a few instants, produces, in twenty to 
twenty-five minutes, a complete dilatation , with immovability of 
the pupil. 
Such a dilatation is desirable and even necessary to obviate 
synechia, synizezis, prolapsus, iridis, etc., and also as prepa- 
ratory to the operation for cataract, in which the pupil has so 
great a tendency to contract. It would also be highly 
advantageous, when it is wished to dilate the pupil, in order 
to examine the deeper seated parts, the lens, the vitreous 
humour, the retina, and the choridea, with the aid of the 
ophthalmoscope ; but there is here an important counter- 
indication, in the marked disturbance of vision which is 
temporarily induced by it. Besides the intolerance of light, 
which annoys some, the seeing of small objects, as in reading, 
is rendered almost impossible for from four to eight days. 
