696 
DE. E. SMITH OX THE CHEMICAL 
I have sought to discover a proportion between the pulsations and respirations 
together and separately on the one hand, and the quantity of ah' inspu'ed, or the 
carbonic acid exhaled, on the other; but by no combinations have I been able to dis- 
cover it. Lavoisiee affirmed that the volume of oxygen consumed was en raison 
directe du produit des inspirations par les pulsations.” I find that half of the product 
of the respirations and pulsations will very nearly represent the number of cubic mches 
of air inspired by myself and Professor Feanklaxd, and in the whole results combmed. 
but it is excessive when applied to Dr. Mueie and Mr. Moll. ^ _ 
The ditference amongst men which has been already noticed in respect to the carbomc 
acid, is equally observable in all other subjects of inquhy. Thus Professor Fe.4XELaxd 
and myself differed in the quantity of air inspired as 3 to 5, and in pulsation as 6 to <. 
Dr. Mueie exhibited the highest proportion of respirations to pulsations, and Mr. Moul 
the least ; the former being the youngest, and the latter the oldest subject of the mqiim . 
' 2. Without food. 
There have been numerous experiments of long duration made on amnials whilst fast- 
ing, all of which have proved that in the absence of food the quantity of carbonic acid is 
reduced. No similar experiments are upon record in reference to Man j but Lavoisiee, 
SCIIAELING, ViEEOEDT, Valextia and others, have shown that when the internal between 
meals is prolonged the same result is obtained. 
On July 6 I fasted from 9-|a.m., after a rather small breakfast (12i hours ha img 
elapsed since the previous meal), until midday of July 7, and made an inqiiiiy into the 
state of the respiration during five minutes at the commencement of each hour, Horn 
1 to 11 P.M. on the 6th, and from 7 to 12 a.m. on the 7th. After having fasted twenty- 
five hours, I wished to ascertain if starch would produce more respiratory changes when 
the system was empty of food than under ordinary circumstances, and I took oOOgrs. 
of arrowroot boiled with 10 oz. of water ; and having found that the secretions were very 
alkaline, I took 6 drachms of table vinegar in water in an hour after hawng taken t le 
starch. The details of this experiment are recorded in Table Y. [See opposite page.] 
The total quantity of carbonic acid evolved gave an average of exactly - grs. per 
minute. If to this quantity, computed for the eighteen hours of the working day, be 
added that previously assigned to the six hours of the night, the total quantity 
carbonic acid evolved in the twenty-four hours will be 21'73702, containing o-9_o oz. 
of carbon. The total average of the twenty-four hours was thus 6-61 grs. per minute, 
and the deficiency from the quantity evolved with food, from the data already gn en. 
was 25 per cent., or one-fourth of the larger quantity. The quantity of carbon thus 
evolved daily in the absence of food is very nearly equal to that contained in 20 oz. ot 
bread, or 7^ oz. of fat. 
The quantity of air inspired during the working day, was on the aieiage o / ^ 
inches per minute. The rate of respiration 10-86, and of pulsation 6b-6 per niinule. 
The diminution, when compared with the experiment with food in May, uas in 
