The term Graphite has been indiscriminately applied to many varieties of native carbon of very different properties. The graphite of New Brunswick differs but little in appearance from anthracite coal. The graphite of Greenland is not very dissimilar, but possesses rather more metallic lustre. However, among these varieties of carbon, two may be especially distinguished,—by a superior degree of metallic lustre, by their structure, and other well-defined properties. In the following paper, the term Graphite is mited to these two varieties, which may be further distinguished as "lamellar” and amorphous.” The lamellar graphite is found in great abundance in Ceylon, whence large quantities are annually imported into this country. It appears in commerce in masses, sometimes of the weight of many pounds, of a brilliant metallic lustre, and possessing a distinct fibrous structure. It is very difficult by mechanical processes to bring this graphite to a fine state of division; however, by a prolonged grinding in water, it may be reduced to minute flat plates. This graphite is associated with quartz. A deposit of the same variety of graphite has recently been discovered at Travancore. The graphite from Travancore has no fibrous structure, but is in the form of slightly coherent, minute dates. Specimens of a similar graphite have also been given to me, from Moreton Bay an Australia, in a matrix of quartz, and from Ticonderoga, in the State of New York, associated with olivine and sphene. When cast iron is dissolved in acid, a residue is eft of about 4 per cent, of carbon in the form of graphite. This graphite also consists of minute brilliant plates, and is perfectly similar in its appearance and properties to the lamellar variety of native carbon. Amorphous graphite is found in Borrowdale in Cumberland, and is also largely imported into this country from Germany, probably from Griesbach near Passau, but I am unable to speak with certainty as to the locality whence it comes. It appears as a powder of a silvery grey colour, soft to the touch, and which rubbed on paper gives a brilliant metallic streak. This graphite is much softer than the other variety, and therefore better adapted for the manufacture of pencils.

Brodie on Diseasea of the Joints. cient and modem works printed in France and elsewhere; and finally a list of some of the works in the store of Rl. Bailliere, presenting their exact titles, con¬ dition and price.. This Bulletin is to appear Quarterly, each No. to contain from 33 to It) pages 8vo. Subscription three francs per annum, it will be a very useful and ac¬ ceptable publication to the medical student.Art. XX_Jt Treatise on Food and Diet.-u-ith Observations on the Dietetical Regi¬ men suited for Disordered States of the Digestive Organs; and an account of the Dietaries of some of the principal Metropolitan and other establishments for pau¬ pers, lunatics, criminals, children, the sick, frc.

No abstract

Background: Pancreatic cancer has a very poor prognosis as most patients are diagnosed at an advanced stage when curative treatments are not possible. Breath volatile organic compounds (VOCs) have shown potential as novel biomarkers to detect cancer. The aim of the study was to quantify differences in exhaled breath VOCs of patients with pancreatic cancers compared with cohorts without cancer.Methods: Patients were recruited to an initial development cohort and a second validation cohort. The cancer group included patients with localized and metastatic cancers, whereas the control group included patients with benign pancreatic disease or normal pancreas. The reference test for comparison was radiological imaging using abdominal CT, ultrasound imaging or endoscopic ultrasonography, confirmed by histopathological examination as appropriate. Breath was collected from the development cohort with steel bags, and from the validation cohort using the ReCIVA™ system. Analysis was performed using gas chromatography-mass spectrometry.Results: A total of 68 patients were recruited to the development cohort (25 with cancer, 43 no cancer) and 64 to the validation cohort (32 with cancer, 32 no cancer). Of 66 VOCs identified, 12 were significantly different between groups in the development cohort on univariable analysis. Receiver operating characteristic (ROC) curve analysis using significant volatile compounds and the validation cohort produced an area under the curve of 0⋅736 (sensitivity 81 per cent, specificity 58 per cent) for differentiating cancer from no cancer, and 0⋅744 (sensitivity 70 per cent, specificity 74 per cent) for differentiating adenocarcinoma from no cancer. Conclusion:Breath VOCs may distinguish patients with pancreatic cancer from those without cancer.

It was on the day following that of the foregoing discussion that our friend invited us to accompany him to a spot in the neighbourhood D * Posthumous Works.-Lectures on Light, sect. 7.