257 
_on the meteorological conditions, but, equally or more, on the condi- 
tion of the woody fiber of the stock and stems. Similarly the date of 
flowering is calculated by assuming, with Gasparin, that the sum total 
of the mean daily temperatures in the shade must be 466° C., count- 
ing from the date of leafing. This number is more especially appli- 
cable to the vineyards of Champagne and Burgundy, and is not 
necessarily strictly applicable to Epernay or to the vineyards of 
the south of France. The fifth and subsequent columns of the 
table give the mean climatic conditions for a period of sixteen days, 
in the middle of which is the calculated date of flowering. There 
appears to be no simple relation between this latter data and the 
resulting wine crop, nor has the crop any apparent relation with the 
total sky radiation during this period. In fact we may conclude that 
up to the time of flowering the energy of the vine has been devoted 
to building up its own structure as a preparation for the work that is 
to come. The development of the grape does not depend upon nitrog- 
enous particles stored away in the vine, but on the power to elaborate 
the sap which is to become the juice of the grape, and that power 
depends upon the leaf surface, the roots, and the stock during the 
first stages of the growth of the grape, but eventually upon changes 
that go on within the grape itself. 
These facts are brought out by the study of the conditions prevail- 
ing during the last stages, viz, from flowering to maturity : 
During 20 days. | During 16 days. 
CoS te oie | Average| otal pel ec of flow- Average | Average | Total 
: jtempera-| ..cinfall. : tempera- radia- | rain- 
ture. ture. | tion. fall. 
ones mm, | oes ° Actin. | mm, 
May 21, 1873_...---.------ | 12.1 Dro lt Manes eee ee eee 18.7 46.1 88.1 
Maye 20s 187422222. 2252-22 H 13.2 PU ts | fea Rudavey 1B} See Se eee Sao 16.8 41.5 26.8 
Mayeos 8 inte s-- = 228 - ee 16.0 DA tay ANE UUs (ey ees Seen eee see 19.0 55. 2 38.3 
Mayas. 1 Si62.---5-.2--.25 14.2 SHOR UM e20) ease | eee cee 19.4 49.0 52.3 
WiaveoloeI Site oc. 2 oe 115 Oath | huhasyibjee See Pee ee 20.9 51.6 18.3 
Maryal6, 1S%Sc se... =. 14.1 Bleve | ume 6 2282 eo eos e | 16.4 40.3 bowl 
Maya ol SiQe 2) ase se 12.6 35.9 | June 22 ___.-_---- 2a eee { 16.6 43.0 ai 
Marya 6:1 S80ka see 3S 14.0 OLOnl itunes 6 =. ees eee ee Pee | 16.2 37.6 45.5 
Marvoel leas a2. 2 22.52 14.6 29:07 Sumer8@.---- =. 22 sesse4 <2 14.9 48.7 15.2 
Average May 18 __-| 13.6 27.5 Average June 16 _- Ue 45.9 40.6 
According to Gasparin the grape reaches its maturity when it has 
received a sum total of mean daily shade temperatures of 1,926° C., 
counting from the date of flowering, but the grape ceases to be 
nourished or to ripen when the mean daily temperature falls below 
12.5°. If, now, we ascertain the date of maturity by summing up 
‘the daily temperatures, as required by Gasparin’s rule, we obtain 
the results given in the first column of the following table. If we 
2667—05 m——17 
