S IJ M A ?r U A. 
vice V'jr^a, If then this .proportion can be kiiov7i% and the ftate of po^ 
pulation in a rcfidency afcertaincd, k becomes eafy to determine the true 
uieditim number of bearing vines in that refidencj'. 
There are, agrceabljr to the form of the furvey bookj eleven ftagefi 
or clafles of vines, each advanced one year. Of thefe clafTesj fix are 
bearing, and €ve young* If therefore the gardens were not liable to 
accidents, but pafied on from column to column undiminiihed* the true 
proportion of the bearing vines to the young, would be as fix to five, 
or to the total, as fix to eleven* But the various contingencies above 
hinted at, mufi tend to reduce this proportion ; while on the other hand, 
if any of the gardens Ihould continue longer than is ncceffary to pafs 
through all the ftages on the ftirvey book, or Jhonlfl remaiu more than 
one year in a prime ftate, thcfc circumftanccs would tend to encreafe the 
proportion. What then is the true medium proportion, can only be 
determined from experience, and by comparing the ftate of a refidency 
at various fuccelEvc periods. In order to afcertain this point, a very in- 
genious gentleman, and able fervant of the Eaft India Company * • to 
whom I am indebted for the moft part of what I have laid before the 
reader on this fubjed; drew out, in the year 1777, a general compa- 
rative view of Manna refidency, from the furveys of twelve years, an- 
nexing the produce of each year* From the ftatement it appeared, 
that the proportion of the bearing vines to the whole number, in that 
diftrift, was no more than 5,1 to 11, inftead rif 6 11, which wodd 
be the proportion if not i educed by accidents ; and further, that wheo 
the whole produce of the twelve years was difFufed over the whole num- 
ber of bearing vines during that period, the produce of one thoufand 
vines came out to be four hundred and fifty three pounds, which muft 
therefore be cftimated as the medium produce of that refidency. The 
fame principle of calculation being applied to the other refidcaciesj it 
appeared, that the mean annual produce of one tlioufand vines, in^l 
the various ftages of bearing, taken caUe^ively throughout the country, 
deduced from the experience of twelve years, was four hundred and 
* Mr* John Crifp. 
