436 Transactions of the Prussian Gardening Society. 



house, take place as to the stoning. The temperature in the 

 open air during that period varies from 48° to 50° Fahr. ? 

 and the temperature in the cherry house should not exceed 

 these two extremes. In the open air, rainy weather often 

 occurs during the stoning period ; and it has been remarked 

 that rain, moisture, and cloudy weather are more favourable to 

 the stoning of the cherry than dry weather. In applying 

 water in the forcing-house to imitate nature, the precaution of 

 placing canvass over the pots and boxes, already mentioned, 

 must be resorted to, otherwise the soil would soon be rendered 

 unfit for the roots. Air must be given liberally ; and, in moist 

 weather, too much damp must be avoided, by the application 

 of fire heat. Gauze covers will require to be as frequently 

 used as during the blossoming period, and the gardener must 

 never think it any trouble to put them frequently off and on. 

 4. From the Stoning to the Ripening. — At Sans-Souci, in the 

 open air, in 1822, the whole process, from the foliation to the 

 ripening of the fruit, lasted from the last week in February till 

 the 17th of June, on which day ripe cherries were gathered. 

 The blossoming period of that season lasted from the 15th to 

 the 24th of April. The swelling of cherries in the open air, 

 therefore, may be considered as taking place in the last fort- 

 night of May and the first fortnight in June ; and an average 

 temperature prevails during that period of, in the morning, 

 50°, noon, 66°, evening, 55°; and the maximum of these 

 periods, 62°, 81°, and 66° Fahr. Continuing to imitate 

 nature in the forcing-house, we have here given what will be 

 found a suitable temperature. Showers are frequent in the 

 last fortnight of May, but the weather is drier in the first 

 fortnight in June, and this also must be imitated. The fre- 

 quent use of the gauze shade is equally necessary. 



Thus it appears that three months and a half, from the 

 first of March, are required to produce and ripen the cherry 

 in the open air ; if we could imitate nature, therefore, perfectly, 

 by beginning on the first of January, we should have ripe 

 cherries by the middle of April. It may be some proof of 

 the power of art, to state that forced cherries, at Sans-Souci, 

 are frequently gathered in March, and sometimes in February ; 

 commencement, in the latter case, being made in December. 

 To a certain extent, therefore, art can improve upon or sur- 

 pass nature. 



" In the foregoing treatise, my chief object has been to show 

 that the process of forcing is founded on a strict imitation of 

 nature, and that the more perfect the imitation, the more 

 perfect the articles produced." 



