66 REPORT — 1855. 



of the latter are well seen in the instances of Bowling and Renfrew, where water of 

 a similar composition is found, at Bowling during every ebb of the tide, and at Ren- 

 frew during flood-tide. The distance between these two places is five miles ; hence 

 at every ebb and flow of the tide, there is a five-mile variation in the composition of 

 the water at these points. In passing further down the Clyde, no doubt this five- 

 mile oscillation in the strength of the water will vary, but at all the places mentioned 

 in the table it will be more or less apparent. 



On the Composition of Bread. By Dr. Maclagan. 



Dr.Maclagan gave the results of some experiments which he himself had made. The 

 amount of moisture in bread was less, and consequently the nutritive value greater, than 

 was generally allowed. The late Prof. Johnston had stated that a sack of flour produced 

 one hundred quartern loaves. But, according to his (Dr. Maclagan's) examination, 

 the sack of 380 lbs. gave 94^ loaves of bread; 100 lbs. of flour giving 231 lbs. of bread. 

 The majority of bakers were of opinion that the sack produced on an average 92 loaves, 

 and there was no great discrepancy between this and the result of his own analysis. 

 Unfermented bread contains, of dry flour, 60 ; moisture, 1 ; water added by baker, 30. 

 100 lbs. of flour will give 143 lbs. of bread, and a sack of flour will yield 100§ quartern 

 loaves of unfermented bread. 



On the Metals of the Alhaline Earths. By A. Matthiessen, Ph.D. 



Dr. Matthiessen has succeeded in preparing the metals strontium and calcium in 

 the form of metallic reguli. The mode of preparation was illustrated by the apparatus 

 used, and beautiful specimens of the metals, sealed up in tubes containing roach oil, 

 and free from all air, were circulated among the members of the Section. Specimens 

 of Lithian wire, prepared by Prof. Bunsen, at whose laboratory at Heidelberg the 

 foregoing metals were prepared, were also exhibited. 



On the possibility of representing by Diagrams the principal Functions of 

 the Molecules of Bodies. By the Rev. J. G. Macvicar, D.D., Moffat, 

 Dumfriesshire. 



In this communication, the author, setting out with a point in the centre of a circle 

 (Dalton's diagram for hydrogen and the astronomical diagram for the sun) to stand 

 for the unit of material nature or minim element out of which all the molecules of 

 bodies might be conceived to be constructed, proceeded to show that nothing more 

 was required in order to arrive at constructions representative of hydrogen, oxygen, 

 sulphur, &c., both as to atomic weight, refractive power, &c., but to combine these unit 

 elements or atoms in such a way as to give a symmetrical construction. 



Then showing that the law of symmetry (which alone he postulated as the grand 

 law of natural synthesis) culminated towards a spherical shell or cell as its limit, he 

 proceeded to combine the representatives of the undecomposed bodies he had con- 

 structed, so that the compound should always be more nearly spherical than its consti- 

 tuents when separate; and thus he obtained diagrams which proved to be represent- 

 atives of vapour, water, monohydrated sulphuric acid, &c. 



He concluded by illustrating the practical value of his method by presenting before 

 the Section diagrams of urea and uric acid, from which it appeared that their transfor- 

 mation was, under the law of genesis according to maximum symmetry, quite a definite 

 problem. 



On the Chemical Composition of some Iron Ores called ' Brass' occurring in 

 the Coal-Measures of South Wales. By E. Chambers Nicholson and 

 David S. Price, Ph.D., F.C.S. 



The ores to which this paper refers are held in low estimation, and even rejected 

 by some ironmasters. It was with a view of explaining the reason of this that 

 their examination was undertaken. 



There are three varieties of this ore. 



I. One is compact, heavy, and black from the admixture of coaly matter; when 

 broken it exhibits a coarse pisiform fracture. 



