1S14.] Scientific Intelligence. 4C9 



moved you will find your tube very neatly and distinctly gra- 

 duated. 



7. Mark with a diamond the figures denoting every tenth degree, 

 and the whole is finished. 



II. On the Term Fluid Qunce. 



I have received the following communication from a gentleman 

 who subscribes himself \V. L. C. 1 may notice that the term Jiiiid 

 ounce to which he objects, was introduced by the London College 

 of Physicians in the last edition of tlieir Pharniacopo^ia, in order to 

 remedy a defect which had previously existed in this country. 

 Weights and measures were formerly denoted by the same names. 

 Fluid ounce, if I remember right (tor 1 have not the Pharmaco- 

 poeia at hand) means the twelfth part of a pint, and is therefore 

 equivalent to 2*406' cui)ic inches. 1 am quite of my correspond- 

 ent's opinion, that such expressions should be avoided in a chemical 

 dissertation, and that cubic inches, which is a measure free from 

 ambiguity, ought always to be employed in preference. At the 

 same time it is not surprising that Mr, Brande, who is Lcctmer to 

 the Apothecaries, and who must in consequence be very familiar 

 with their measures, should make use of such expressions. 



" The term '■ Jin'id ounce,' frequently employed by a learned and 

 ingenious chemist, in his Reiertrches on the Blood, and other papers 

 contained in the latter volumes of the Philosophical Transactions, 

 appears liable to some objections in point of philulogical accuracy : 

 it is used to signify a measure of any liquid equal in volum.e to an 

 ounce of water, whereas the obvious sense of ihe words is, an ounce 

 in vveight of a sul)stance in a fluid state. It would be preferable to 

 express the quantity in cubic inches, and instead of one fluid ounce, 

 to say l-p'uV^ culiie inches ; instead of two (luid ounces, .'5-fij'^^- cubic 

 inches. Jn order to avoid fractions, measuring vessels maiked with 

 the cubic inch and its multiples, ought to be employed in place of 

 those marked with the ounce of water." W. L. C. 



SIR, 



III. Aiitiluiiar Tide. 



(To Dr. Thomson.) 



It appears to me that tlie two principles of gravity and projectile 

 force account in a very satisfactory manner for the antilunar tide. 



If a fluid body move in a circle round any centre, (its centrifugal 

 force counteracted by gravity) it will assume a form nearly sphe- 

 roidal.* For its centre of gravity is that part where the two forces 

 are counterbalanced ; consequently, the furihcr part of it h;is 

 greater cetitrifiig;d than centripetal force, and would Hy off, were it 

 not rcstrair)ed by tl;e general mass; and the neaver part of it has 

 more centripetal than centrifugal force, and would fall towards the 

 centre, were it not restrained by the satne cause. For the same- 

 reason that a fluid body turning on its axis assumes the form of an 



• The prMlcr IIk* dirlanrp hj-twcfii two revolving bodiw, othfp lhin;;» ro 

 Riaiiiing tlic laiuc, Ihc mure iicailv will lluir forms a|niri»ucli to iptUTuiiU. 



