8 NUTRIENTIA. ART. I. 2. 2. 4. 



,4. The rcafon why autumnal milk is fo much thicker or co- 

 agulable than vernal milk, is not uneafy to underftand ; but asnew 

 milk is in many refpefls fimilar to chyle, it may be confidered 

 as food already in part digefted by the animal it is taken from, 

 and thence fupplies a nutriment of eafy digeftion. As it requires 

 to be curdled by the gaftric acid, before it can enter the lac- 

 teals, as is feen in the ftomachs of calves, it feems more fuita- 

 ble to children, whofe ftomachs abound more with acidity, than 

 to adults ; but neverthelefs fupplies good nourifliment to many 

 of the latter, and particularly to thofe, who ufe vegetable food, 

 and whofe ftomachs have not been much accuftomed to the un- 

 natural ftimulus of fpice, fait, and fpirit. See Clais I. I. 2. 5. 



III. i* The feeds, roots, leaves, and fruits of plants, confti- 

 tute the greateft part of the food of mankind j the refpecSHve 

 quantities of nouriftiment which thefe contain, may perhaps be 

 eftimated from the quantity of ftarch, or of fugar, they can be 

 made to produce : in farinaceous feeds, the mucilage feems grad- 

 ually to be converted into ftarch, while they remain in our gra- 

 naries *, and the ftarch by the germination of the young plant, 

 as in making malt from barley, or by animal digeftion, is 

 converted into fugar. Hence old wheat and beans contain 

 more ftarch than new ; and in our ftomachs other vegetable and 

 animal materials are converted into fugar ; which conftitutes in 

 all creatures a part of their chyle. 



Hence it is probable, that fugar is the moft nutritive part of 

 vegetables *, and that they are more nutritive, as they are con- 

 vertible in greater quantity into fugar by the power of digeftion ; 

 as appears from fugar being found in the chyle of all animals, 

 and from its exifting in great quantity in the urine of patients 

 in the diabetes, of which a curious cafe is related in Seft. XXIX. 

 4. where a man labouring under this malady ate and drank an 

 enormous quantity, and fometimes voided fixteen pints of water 

 in a day, with an ounce of fugar in each pint. 



The nutritive quality of fugar is not only (hewn by the flaves 

 in Jamaica, and other animals, becoming fatter in the fugar 

 harveft, though they are forced to labour more, but alfo from 

 the many inftances of its nourifhing for fome years very old 

 people, who could take little of any other food. Many of 

 which cafes are recorded in Dr. Mofely's Treatife on Sugar, 

 and three I have myfelf witnefled. 



Nor is this to be wondered at, as it conftitutes a part of the 

 chyle both of vegetables and animals ; which only feem to dif- 

 fer from each other in this circumftance, that the chyle of veg- 

 etables confifts principally of fugar and mucilage diflblved in 

 water j as the juice extracted from birch and maple-trees in 



the 



