336 . REPORT—1852. 
the extreme cases, to as much as from one to three and a half. There can be 
little doubt that the method of estimating the amount of available nitro- 
genous substance from the per-centage of nitrogen must be more or less faulty, 
both in the case of the succulent turnips of the first series, and in that of the 
also unripened produce—clover-chaff—of the second; but whether or in 
what degree the differences in the amounts consumed in the two series would 
be lessened by corrections due to this source of discrepancy, we have not the 
means of accurately deciding. 
In the third series, which consisted of five pens, mangold-wurtzel was the 
complementary food ; and the limited foods were barley and malt, respectively, 
in different states and-proportions in the several pens. Throughout this series 
the proportion of nitrogenous to non-nitrogenous constituents varied but 
little in the limited foods, and being also constant in the complementary foods 
of the several pens, we have but little difference in this series in the amounts 
respectively of either class of constituents when comparing pen with pen. 
Comparing the results of this series with those of the others, however, we 
observe that there was a very close coincidence between the amounts of avail- 
able zon-nitrogenous substance consumed; but in those of the nitrogenous 
substances there is little in common when thus taking at one view the results 
of the several series. 
In the fourth series we have no supply of limited food. In all the four 
pens Norfolk-white turnips only were given ad libitum. Those supplied to 
the different pens, were however, respectively grown by very different manures, 
and differed in all cases very much in ultimate composition and other 
qualities. Thus, the per-centage of dry substance and the state of maturity 
were greatest in the turnips of pen 1, and diminished in the order of the pens, 
they being in pen 4 the worst in both these respects. On the other hand, the 
per-centage of water, of mineral matter, and of nitrogen, and the degree of 
unripeness or unfitness for food, were in the inverse order. The turnips eaten 
in pen 1 were, however, too ripe, and what is called “‘ pithy”; and those 
were in the best condition which were supplied to pen 2. 
In this series there was, with a probably generally lower amount of effete 
matter, at the same time a generally less amount of non-nitrogenous substance 
consumed—though most where the turnips were known to be too ripe and 
pithy. In pen 4 there was a very small amount of non-nitrogenous substance 
taken ; but thereis no doubt that here the limit to consumption was fixed by 
the unfitness of the turnips as food, and not by their high value in this respect; 
for these turnips were very succulent and unripe, and notwithstanding they 
contained a very high per-centage of nitrogen, all the animals fed upon them 
lost weight. Taking the circumstances into account, then, we have as much 
uniformity in the amounts of non-nitrogenous constituents consumed as we 
could expect, both among the several pens of the series, and in comparing this 
series with the rest. In the column of nitrogenous constituents, on the other 
hand, there is nothing to indicate any uniformity of demand for the supply 
of them, whether we compare pen with pen, or the results of this series 
with those of the others. It might perhaps be objected, from what we have 
already said of the varying qualities of the turnips used in this series, that 
the nitrogenous compounds themselves would exist in the different lots in a 
more or less assimilable condition; and hence probably some of the differences 
in the amounts consumed. Doubtless there were differences in this respect 
in the different lots, but it is seen that there is nearly twice as much of nitrogen 
consumed in one pen as in another; and we cannot suppose that by any such 
method of correction as has been suggested, so large a differeace as this, 
or even that the whole of the lesser ones observed in the other cases, could 

