WATER IN DIFFERENT VARIETIES OF TURNIP. 525 



aid of diffbrent manures, nor, consequently, the true effect of these 

 manures upon the relative values of the several crops. 



4°. Quantity of water in different varieties of turnip. — The same re- 

 mark may be made in regard to the several varieties of turnip. All 

 those examined by Hermbstadt, as appears from the above tables, con- 

 tained 20 to 22 per cent, of solid matter (78 to 80 of water), while other 

 experimenters have found as little as from 8 to 15 of solid matter in tur- 

 nips, and generally less in the white and large globe turnip than in the 

 yellow and more solid Swede. 



Thus, four varieties of the above roots^ contain of water and solid mat- 

 ter, according to three different experimenters : — 



WATER PEH CENT. DRY MATTER PER CENT. 



Einhof. Playfair. ^^^ermb- Eiuhof. Playfair. ^Jf|S!"" 

 White turnip 92 90 79 ' 8 11 21 



Swedish do. 87^ 85 80 12| 15 20 



Cabbagedo. 8G — 78 14 — 22 



white. 

 Carrot . . 86 87 80 14 13 20 



The above differences are very great, especially when we look to the 

 relative proportions of dry matter in which the nutritive power resides. 

 They are of much importance, therefore, to the feeding of stock, and 

 the circumstances under which they occur, are deserving of a careful in- 

 vestigation. 



5°. Relative nutritive properties of the potatoe and the turnip. — The 

 potatoe is usually considered more nutritive than the turnip, weight for 

 weight, and no doubt it generally is so. But if we compare together the 

 quantities of solid matter which the two roots may contain, we shall see 

 how very far wrong our estimate may be in any special case. Thus — 

 The turnip contains of solid matter from 8 to 22 per cent. 



The potatoe do. do. 24 to 32 " 



— so that, while the driest turnips may contain four times as much solid 

 matter as the most watery potatoes, very dry potatoes m.ay contain 

 nearly as much as very jiiicy turnips. It is impossible, therefore, with- 

 out an actual examination of the samples, to pronounce upon the relative 

 amount of food which is likely to be contained in any equal weights of 

 turnips and potatoes. The very discordant estimates which different 

 feeders of stock have formed in regard to the relative value of these 

 crops in the production of beef or mutton is partly owing to this cause. 

 [Other causes for these discordant estimates will be .stated in Lecture 

 XXL] Until the effects of equal weights of the different kinds of food, 

 estimated in the dry state, are carefully ascertained, it will be impossible 

 to obtain results of- a general kind or upon which any real confidence 

 can be placed. 



§ 23. Of the composition of the green stems of peas, vetches, clover, spurry^ 

 and huck-wheat. 

 The stems and leaves of plants which are given as green food to 

 animals differ much in composition, according to the age they have at- 

 tained, to the rapidity of their growth, to the nature of the soil, the 

 season, and the mode of culture. They are generally supposed to be 

 richest in nutritive matter when the plant has just come into flower: 



