SCIENTIFIC SUMMAKT. 
429 
The sulphates increase inland before large towns are reached. The sulphates 
rise very high in large towns, because of the amount of sulphur in the coal 
used, as well as decomposition. When the air has so much acid that two 
or three grains are found in a gallon of the rain-water, or forty parts in a 
million, there is no hope for vegetation in a climate such as we have in the 
northern parts of the country. Free acids are not found with certainty 
where combustion or manufactures are not the cause. Experiments in the 
direction indicated above may enable us to study and express in distinct 
language the character of a climate, and certainly of the influences of cities 
on the atmosphere.” — Fifth Report published by Spottiswoode, and presented 
to both Houses of Parliament. 
To prevent Bumping in Boiling. — The hete noire of chemists is the pheno- 
menon known as bumping. The following method of preventing bumping 
has been described ,,by Dr. Hugo Muller in the Chemical News (July 30), 
and deserves trial : For ordinary purposes I have found it still more 
convenient to introduce into the liquid about to be distilled a small frag- 
ment of sodium amalgam, or, in cases where the liquid is acid, a small piece 
of sodium-tin. Methylic alcohol is well known to be one of the most difii- 
cult liquids to distil, yet on the introduction of a minute piece of sodium 
amalgam or sodium-tin it can be distilled without the slightest inconve- 
nience. I found on one occasion that more than 400 grammes of methylic 
alcohol distilled over with perfect steadiness, and without exhausting the 
activity of a fragment of sodium-tin, weighing not more than 0-060 grms. 
It is, perhaps, hardly necessary to mention that the action of sodium 
amalgam and sodium-tin is due to a minute but continuous disengagement 
of hydrogen taking place during the process of distillation.” 
Apomorphia is the name of the curious compound obtained by Dr. 
Matthiessen from morphia, by acting on it with acids at a certain tempera- 
ture. It has no narcotic properties, but is a most powerful emetic. The 
discoverer’s account is published in the last number of the Proceedings of the 
Royal Society. 
Researches on Vanadium. — The second part of Prof. Eoscoe’s valuable 
paper (the first part was the Bakerian lecture for 1868) was read at the last 
sessional meeting of the Royal Society. 
The new Chemical Chair in Anderson's University. — A new chair has just 
been founded by Mr. Young (of parafin oil celebrity, we believe) in this 
private university. It is a chair of technical chemistry, and has been given 
iDy Mr. Young to his friend Mr. W. H. Perkin, the celebrated discoverer of 
the coal-tar colours and Secretary to the Chemical Society. The chair is 
worth about 300/. a year. 
A new Dye from Madder. — Though it is probable that the newly dis- 
covered artificial alizarine will do aw^ay altogether with the cultivation of 
madder, it is interesting to learn that a new colour has been obtained from 
this plant. Prof. Rochleder, at Prague, has found that, when madder is 
treated with dilute mineral acids, it yields, beside alizarine and purpuriue, a 
small quantit}^ of a third tinctorial substance, which, in alkaline solution, 
has a great similarity to chrysophanic acid dissolved in alkaline solurion ; 
acids precipitate it from this solution in the amorphous flocculent shape, the 
precipitate being of a pale yellow colour. This substance is soluble in 
