396 



Mr. Tidnias on the Proportion of Nutrition 



[June I, 



To the Editor of the Monthly Magazine. 



SIR, 



IN " Moore's Almanack Improved," 

 for the present year, is an account 

 of the nourishment contained in vari- 

 ous kinds of food; the writer of the 

 statement observes, " and what is very 

 remarkable, as being in opposition to 

 the hitherto acknowledged theory, a 



(I speak by conjecture,) twenty-four 

 pounds per day of green or succulent 

 vegetables; this quantity would be 

 said to contain but two pounds of 

 solid nutritious substance, or about 

 one-twelfth part of the whole: but 

 does not this evince a most egregious 

 fallacy?" Certainly not: but if Mr. 

 Luckcock chooses to make a very 



hundred pounds of potatoes yield only absurd conjecture, and then reason 



twenty-five pounds of substance va- 

 luable as nutrition." Now I consider 

 this an error of importance, as likely 

 to prejudice some persons against a 

 most useful vegetable, and therefore 



upon it as thoTigh it were a fact, he 

 must expect to arrive at very absurd 

 conclusions. Pray what right has 

 Mr. Luckcock to conjecture, that a 

 cow consumes only twenty-four pounds 



begtoobserve, that there is no acknow- of succulent vegetables per day? To 



ledged theory whatever against which 

 the above fact militates. Ever since 

 the elaborate analysis of Dr. Pearson, 

 which appeared in (I think) the tiiird 

 volume of the " Repertory of Arts," it 

 has been well known that potatoes 

 contain, according to their kind, from 



write on subjects of which we are ig- 

 norant is at all times ridiculous ; but 

 it is particularly so when the means of 

 knowledge are so completely within 

 our reach. Now the most common 

 works on agriculture inform us, that a 

 cow of medium size requires daily 



twenty-five to thirty-two per cent, of twenty-five pounds of hay or dry food, 



solid matter, the remaining portion 

 being merely water ; and the accuracy 

 of this analysis has been verified by the 

 subsequent one of Einliof : how absurd, 

 in the face of this fact, to talk of an 

 acknowledged theory ;" who ever 



the equivalents for which in succulent 

 vegetables are 100 lbs. of green clover, 

 180 lbs. of cabbage or turnips, or one 

 busliel of potatoes. Now 25 lbs. of dry 

 food per day amounts to 9,125 lbs. per 

 year ; in return for which, the cow, 



acknowledged any theory but the sim- after sustaining herself, produces about 



pie fact, that potatoes contain twenty- 400 lbs. of cheese, and about 100 lbs. 



five per cent, of solid matter? Pota- of whey-butter, which is all, or nearly 



toes, indeed, have not derived their so, the solid matter furnished by a cow 



value from containing much nourish- 

 ment in a small bulk, but from pro- 

 ducing a greater quantity of nourish- 

 ment per acre than any other crop 

 cultivated as food for man ; and of this 

 fact the editor of Moore's Almanack 

 may readily satisfy himself, by com- 

 paring an average crop of potatoes 

 with one of wheat : the potatoes ex- 

 ceed the wheat in the proportion at 

 least of four to one ; in this consists 

 their value. 



in one year. Now what is there so 

 very wonderful in all this? I confess 

 that my eyes are not so acute as Mr. 

 Luckcock's ; for I can discern nothing 

 like " egregious fallacy." 



It appears to me that IMessrs. Percy 

 and Vauquelin have confounded the 

 nutritious with the solid matter, con- 

 tained in the articles upon which their 

 experiments were tried ; as, in seven 

 articles out of the nine of which their 

 list consists, the amount of nourish- 



I beg also to make one remark on a ment corresponds precisely with the 



letter, which appeared in your Maga- solid matter furnished by the sub- 



zine for March last, on this suhject ; stances, after they have been dried at 



and, by the way, if the writer of it is the greatest heat, not sufficient to de- 



the same Mr. Luckcock who, two or compose them. Now solid matter is 



three years ago, stated that an acre of not all nutritious; for, if it were, it 



rhubarb was worth I forget how many would of course all be converted into 



thousand pounds, I think he need not nutriment, and none of it excreted, 



in future go out of his road to ridicule This we know is not the case, and yet 



" the hypotheses and calculations of the portion excreted is composed of 



exuberant imaginations." the same elementary matter as that 



The remark I have to offer is on Mr. which is assimilated. What, then, is 



Luckcock's most extraordinary mode 

 of reasoning, which, that I may not 

 misrepresent, I shall quote his own 

 »ords : — " Suppose a cow to consume 



the law of combination? 



I am well aware that, in the whole 

 range of science, there are no enqui- 

 ries so obscure in their investigation, 



and 



