484 THE GARDENER. [Nov. 



pollen appears in most abundance, and that the berries set best. Per- 

 haps, when we know all, it will be found that Mr Simpson thus runs 

 up the heat of his vinery for the better half of the day ; and if we are 

 correct in our supposition, then the relationship of 50° to the setting 

 of his Muscats will appear in its true light. 



It has been our experience in a long practice under divers circum- 

 stances, that Muscats have, without an exception that we can remember, 

 set best when they have been subject to a high temperature for the 

 greater part of the twenty-four hours. Not only so, but they have 

 always set best at the hottest end of tlie vinery and nearest the pipes, 

 as in the case of J. W. B., related in the ' Gardener' of last month. It 

 would be interesting to know how Mr Simpson manages always to get 

 his temperature down to 50° after a warm day and the application of 

 fire-heat in May. We cannot do it, practising much farther north. We 

 presume, from the condition of his Grapes about the middle of Sep- 

 tember, that his Vines are not more advanced than in bloom in May. 



Not to go any further back in our experience, we had a house of 

 Muscats in bloom last May, when the weather was exceptionally cold 

 and sunless, — circumstances under which we think it best to force more 

 gently. Those at the warm end of the house set perfectly, while three 

 rods at the exposed gable and cold end set so ver}"- imperfectly that 

 there were not sufficient impregnated berries to make up the bunches. 

 Will Mr Simpson explain the reason of this ? The Vines were the 

 same variety, and all their circumstances exactly the same, except that 

 the one was in a very much colder atmosphere than the other when in 

 bloom. What is the opinion of other Muscat-growers ? 



We do not controvert the fact, that it is best for plants to treat them 

 to a lower temperature at night than by day. Nature leads the way 

 in this very forcibly ; and it has been practised and written about as 

 long back as we can remember — forty years at least. But nature does 

 not teach us that it is the damp cold air of night that develops the 

 pollen, and is directly to be credited with the setting process. We 

 learned this quite forty years since from Dr Lindley : " It will be 

 found that no pollen is scattered in cold weather, but in a sunny, dry, 

 warm morning the atmosphere surrounding plants is, in the impregnat- 

 ing season, filled with grains of pollen discharged by the anthers. In 

 wet weather the anthers are not sufficiently dried to shrivel and dis- 

 charge their contents," &c. Because of this there is nothing the Vine- 

 growers of France dread more than a wet, cold, sunless time when 

 their Vines are in bloom ; for the bunches, instead of flowering properly 

 and developing pollen, do what the Vine-growers call "run." De- 

 caisne refers to this fact in his work on botany, when treating of 

 physiology. It has long been well recognised that when the bunches 

 of Grapes have a tendency to be "wiry" and "run," that the best 

 way of checking this tendency is to keep them rather warmer and 

 drier instead of colder and damper. We have advocated compara- 



