like good cultivation and manuring, which, while developing the productive force of the vine, are far from exhausting it.

In any case, nothing is more worthy of interest than the study of questions arising out of the use of sulphur to stimulate vegetation. It is a wholly new field, in which the student of vegetable physiology and agriculture may find numerous subjects of observation.

REVIEW OF THE CHAPTERS WHICH RELATE TO THE EMPLOYMENT OF SULPHUR AND ITS ACTION ON THE

VINE.

In this review we see that the action of sulphur on the vine is exerted in two ways quite distinct.

In the first place, sulphur destroys the little parasite mushroom (oïdium Tuckeri) whose development on the branches and fruit constitutes the disease.

In the second place, sulphur acts by exciting vegetation and favoring fructification.

Thus two distinct properties reciprocally complete each other when the disease is to be combated.

The sulphurings should therefore be so timed and regulated as that the one should work to the advantage of the other.

Thus we should always sulphur at the period of blossoming, in order that the fructification should

operate more completely, and this without regard to the disease. If, before or after this is done, the oïdium makes its attack, it will be sufficient, independently of the sulphuring at blossom-time, to give another each time the first symptoms of disease show themselves. I have described them minutely, and, besides, every one knows them too well at the present day to make any mistake.

I have shown by numerous examples that in the most obstinate cases it is rare that four sulphurings, are necessary, not counting that given at blossomtime; that oftener it suffices to add one or two only to this last, in order to obtain the best results. We have also seen how the surveillance of a large vineyard, of varieties the most diverse, is made easy, by keeping a memorandum of the fields in cultivation, and of the sulphurings given them; for the study of the oïdium proves that its reappearances are almost always separated by an interval of twenty to thirty days, according to the intensity of the disease, the variety, soil, cultivation, and temperature.

Thanks to this system, I have indicated how the application should be made to all the varieties of most importance in the South of France; how we may be always in time, always sure to succeed. We realize the greatest possible economy, and do not, all

at a time and needlessly, employ an excessive force of laborers at seasons when they are so scarce that often the most urgent labors must go undone.

For those who would free themselves from the trouble of watching over their vines, and care little about the additional expense-who prefer a rule ready made--there is another manner of procedure equally sure it is to apply sulphur to their vines every twenty days, beginning at the moment when the shoots have attained the length of two inches, and continuing till the grapes begin to color. In the climate of Montpellier these two epochs are comprised between the 1st of May and the 10th of August, or thereabout. In that interval of a hundred days there will be five or six sulphurings to make, whose effects will be assured, as well for the purpose of destroying the oïdium as for that of favoring the vegetation and fructification of the vine. By this system, which is based on the interval which separates ordinarily the reappearances of the oïdium, the average cost of material and labor will be double that which I have given as the highest estimate.

OBJECTIONS AGAINST THE USE OF SULPHUR.

The principal objections made against the employment of sulphur are the following:

1st OBJECTION.—The good effects are doubtful.

If the good effects are doubted by any, it is because they have not made the application under the proper conditions; either their vines had been too long invaded, or the sulphuring was not soon enough renewed and at the opportune moment, or it was incompletely done, and directed against the diseased grapes only instead of all the fruit and entire foliage. It is probable that later, when the employment of sulphur shall have become more general, and we understand better its management, no one will seriously dispute its value.

In all the course of this work I have demonstrated by direct observation, or by practice and the production of facts, how ill founded is this objection. I will add to these a few considerations to answer the arguments of those who tell us they every year see diseased vines cure themselves spontaneously without any sulphur, and that if those which are sulphured recover, it is not the sulphur that cures them, but Nature.

There are vines, it is true, which rid themselves spontaneously of disease; nevertheless, they are never entirely delivered from it, and for that reason are not comparable for strength and beauty to the same vines treated with sulphur. We know them as soon

as we look at them. We always see numerous traces of the oïdium on their grapes, but principally on their shoots. If they pass for being spontaneously cured, it is not so much because we see no oïdium appear upon them as because they give a better crop than in preceding years. It would be more proper to recognize in their condition a marked amelioration than a cure. The number of vines really cured spontaneously is small.

But, in any case, spontaneous cure and sulphur cure are two things which do not conflict at all, especially when that which passes for spontaneously cured, like that which is cured by sulphur, is subject to be again attacked by the disease. Finally, comparative experiments made on the same vine divided in two parts, of which the half which was sulphured was perfectly preserved, while the other half, left to itself, was completely ravaged, answer all objections. Such comparative experiments were often repeated in 1854, 1855, and 1856.

2d OBJECTION.-The use of sulphur is expensive. I have replied in advance to this objection, and proved that such expense hardly amounted to a fourth or a seventh of the ordinary current expenses of a vineyard, including interest, taxes, etc. It is, nevertheless, no trifling expense, but it is very largely