40 REPORT—1846. 
fused chloride of calcium. The carbonic acid was estimated by the loss of weight on 
treating a portion of the mineral with dilute acid in a little bottle connected with a 
tube containing chloride of calcium. 
The solid constituents were determined by ordinary methods. The result was, in 
100 parts,— 
Magnesia ......ssccsensecee 57°86 
Protoxide of iron......... 2°84 
SillGbcesccertatecttesSaneene. 0°80 
Water 7%, cctecaedaae cess cate 27°96 
Carbonic acid .........00. 10°00 
99°46 
Considering the protoxide of iron to replace a little magnesia, the mineral appears 
to be a combination of hydrate of magnesia and hydrated carbonate of magnesia. 
The formula 5MgO, HO + MgO, CO?, HO will nearly express its constitution, and 
gives— 
Magnesia ...sssssceeeeeeees 61°67 
IV SECT nc 'csr sinre Seaaeate 27°24 
(CAaTbDONICACIA secescesenss 11°09 
100°00 
The native hydrated carbonate of zinc (zinkbliithe) is a mineral of analogous con- 
stitution. 
Observations on the Nature of Lampie Acid. By Prof. Conn 1, F.RS.E. 
The author had shown some years since that a large quantity of formic acid and 
a little acetic acid exist in lampic acid as prepared in the ordinary way. Marchand 
and others, admitting the presence of these acids, maintain that in addition it con- 
tains aldehydic acid. It appears however to Professor Connell that the mere reduc- 
tion of oxide of silver without effervescence, the formation of resin with alkaline 
solutions, the blackening of the lampic salts on evaporation and by the action of sul- 
phuric acid, are insufficient to support this view; and these facts are all explained 
on the idea of aldehyde being associated with the acetic acid present in the liquid. 
Further, the atomic weight of lampic acid, 50°35, is much too high to belong to an 
acid, containing aldehydic acid, associated with much formic acid. But if we sup- 
pose a foreign body, such as aldehyde, associated with the acetic portion of the 
liquid, and entering for the time into the constitution of its salts, we can easily ex- 
plain the high atomic weight and chemical reactions. 
On the Connexion between the Isomorphous Relations of the Elements and their 
Physiological Action. By James Buaxe, MB. F.R.CS. 
In a paper read before the Academy of Sciences at Paris, the author remarked 
“that when introduced directly into the blood, the salts of the same base appear to 
exert the same effect on the animal ceconomy.”’ Since that time further researches 
have led to the discovery of a law, equally interesting under a chemical as under a 
physiological point of view. The law alluded to is that, when introduced into the 
blood, all isomorphous substances produce analogous effects and give rise to the same 
reactions in the animal ceconomy. This law has been verified by an extended series 
of experiments with the salts of magnesia, lime, manganese, iron, cobalt, nickel, zinc, 
cadmium, copper, bismuth, lead, baryta, strontia, soda, silver, potash, ammonia, 
palladium, platinum, osmium, iridium, antimony,—the acids of phosphorus, arsenic, 
bromine, chlorine, iodine, sulphur, and selenium. One of the facts observed is the 
connexion which exists between the physiological action of these substances, and 
their isomorphous relations to the elements of the blood. It is found that those 
substances which exist in the blood, or which have isomorphous relations with its 
elements, give rise to the least marked reactions: thus phosphoric and arsenic acids 
can be introduced into the veins without producing any marked phenomena, whilst, 
on the other hand, those elements which are most distinct in an isomorphous point 
aa 
