TBANSACTIONS OF THE SECTIONS. 85 



Refening to a suggestion made by ^h: Lebour, of the Geological Survey, in a 

 paper " Ou tlie Geological distribution of goitre in England and Wales," that the 

 cause of goitre "is the metallic impurities in the water," and a statement "that it 

 prevailed most where ferruginous water occurred," the author states that iron 

 medicinally administered produces beneficial effects, but when fen-uginous water is 

 taken daily it produces a low state of health, and in that way might predispose to 

 the formation of goitre ; but such water would not cause anremia. He observes 

 that it is very doubtful, however, if water containing iron is ever used as a potable 

 water or for culinary pui-poses, one grain per gallon rendering it unfit for making 

 an infusion of tea. 



In the neighbourhood in which he lives such water is avoided. In the per- 

 formance of his duties as Medical Officer of Health, he had chemically examined 

 ten public wells in his district ; and he did not detect a trace of iron in one of them, 

 from which he concludes that goitre, which is very prevalent in the locality, can- 

 not be caused by ferruginous water. 



As anfemia is a state of the system in which oxide of iron is deficient in the 

 blood, and as goitre appears at a time of life and under conditions of the system 

 when a maximum quantity of nutritious food is required, he concludes that where 

 there is a deficiency of iron and phosphates, or nutritive salts in the food, these 

 forms of disease will prevail. 



By chemical analysis he has shown that iron and the phosphates are deficient in 

 wheat grown upon the Carboniferous system compared with that grown upon the 

 New Red Sandstone. Soils, he observes, are formed by the disintegration of the rocks 

 or formations upon which they lie, and consequently they consist of the same in- 

 gredients. The colouring-matter of the Cheshire sandstone is oxide of iron ; and 

 the soil upon it is thoroughly impregnated with that oxide. The Carboniferous 

 SJ^stem is not impregnated with it ; oxide of iron is not so thoroughly diffused 

 throughout this system as it is in the New Red Sandstone ; so, compared with 

 the latter, there is a deficiency of iron in the soil upon the former. 



To the above rule he states there are, however, exceptions, as soils do not 

 alwaj's consist of the disintegrated rocks upon which they rest. In a district with 

 which he is well acquainted the geological formation is Millstone-grit, yet the soil 

 upon it is as highly coloured with oxide of iron as that upon New Red Sandstone 

 at no great distance from it. In this district goitre and anaemia are unknown. 

 He concludes that goitre and antemia do not occur in a district having a soil con- 

 taining a maximum quantity of oxide of iron and phosphates, no matter what the 

 system is upon which it rests. 



On the Ainmonitic Sjyircd in reference to the power of Flotation attrihxUed to 

 the Animal. By John Phillips, M.A., F.Ii.S., D.C.L. Oaon., LL.D. 

 Cambr. and Dublin, Professor of Geology, Oxford. 



The author, while considering the subject in connexion with the recent Nmdihis 

 pomjjiHt(s and Spirrila and with many fossil genera, found a deficiency of data as 

 to the proportion of the supposed air-chambers to the whole volume of the shell 

 and the part of it occupied in life by the animal. To obtain such data he examined 

 the spiral structure by means of principal sections on the plane of volution, and 

 found that, omitting the earliest small volutions, the growth of the ammonite shell 

 was in manj' species uniform, so that the proportion oif the last chamber to the sum 

 of all the preceding ones was nearly uniform ; but among different species the 

 character of the spiral difi'ered. In one group the breadths of the volutions measured 

 on a radius vector increased in geometrical proportion ; in another the increase was 

 in arithmetical proportion ; between these two forms all ammonitic spirals appeared 

 to be contained. The author then showed how, in the former group, the power of 

 flotation, if it existed, would be uniform through life, but in the latter continually 

 increasing. In order to see the exact bearing of this on the question of flotation, it 

 would be necessary to determine some other points as to the thickness of shell and 

 number of septa. 



With respect to the further function attributed to these animals, that cf 

 rising and falling at pleasure in the sea, the author showed, by measuring the 



