Mr. T. Dickson on Inorganic Constituents in Ale and Porter. 34 1 



mical causes, that is in general physical causes, for its explana- 

 tion. It is not, however, my intention to enter rashly on any 

 such speculation, though I think myself justified in at least 

 drawing attention to the simultaneity of the two great phe- 

 nomena here alluded to, namely, the first fall of aerolites and 

 the commencement of glacial action, leaving it to astronomers 

 to decide how far it is possible, under the present most generally 

 received theory of aerolites, as being either condensed nebulous 

 matter, or planetary fragments moving regularly in an orbit, 

 that either the one may have been the cause of the other, or 

 both the effects of some one great common cause. 



LII. An Inquiry into the Amount of Inorganic Constituents 

 contained in Ale and Porter. By Thomas Dickson, Man- 

 chester, late Assistant in the University Laboratory, Edin- 

 burgh *. 



THE object in view in commencing the series of analyses 

 given below, was to ascertain if a standard could be 

 formed of the nutritive powers of the ales and porters in ge- 

 neral use, in order that a correct estimate of their real value 

 as an article of diet might be deduced. 



The analyses show, as might have been expected, a very 

 great variety in the amount of their respective constituents, 

 partly arising from the various modifications each brewer finds 

 himself under the necessity of adopting, from local circum- 

 stances over which he has no control, or from personal ex- 

 perience, though the main steps of the process are essentially 

 the same throughout. • 



The ash consists of that portion of the grain, and other sub- 

 stances employed in the process, which is soluble in water; 

 whilst owing to the various proportions of malt and water 

 employed, to the length of time the infusion is continued, to 

 the temperature at which the infusion is made, to the con- 

 centration the liquor undergoes in the boiling to which it is 

 subsequently subjected, and to the process of fermentation, 

 the proportional amount of the constituents varies considerably. 



The method given by Fresenius and Will for the analysis 

 of Ash was that followed in the present instance. The amount 

 of iron has been omitted, as in most of the cases it was alto- 

 gether wanting ; and in the few instances in which it did occur, 

 it was so minute as to be inappreciable, and apparently was 

 only an accidental impurity. 



In order to save needless repetition, the analyses have been 

 calculated after the deduction of the carbon and moisture, and 

 are as follows: — 



* Communicated by the Author. 



