18 
ON MAGNESIUM. 
bably results from the extraordinary intensity of the light, apart from its useful photo¬ 
graphic property, for, side by side with the magnesium light, the wax candle-flame looked 
not much brighter than the red granite of the walls of the room. There come parties 
often many parties—of visitors to see the Pyramid every day without fail, and they come 
amply provided, too, with all sorts of means and appliances to enjoy the sight, i. e. with 
everything but the needful magnesium wire ; and one waistcoat-pocket of that would be 
worth a whole donkey-load of what they do bring up to enable their souls to lealize the 
ancient glories of the internal scene. 
“ I remain, yours very truly, 
11 John Spiller, Esq., Chemical Department, . C- Piazzi Smyth. 
Royal Arsenal, Woolwich.” . 
M. Nadar is said to be engaged on a series of photographs of the Catacombs of Paris ; 
various artists are busy practising on monuments in obscure recesses of Continental 
churches; and Mr. Brothers, we believe, contemplates undertaking the caves of Derby¬ 
shire. The crypt of St. Stephen’s Palace of Westminster, recently restored and decorated 
under the direction of Mr. E. M. Barry, has been lighted up for an hour and a half with 
the magnesium lamp, and the exquisite elaboration of its moulded and carved doorways 
and the bosses of the groining displayed in vivid detail. By the same means the vast 
recesses of the Outfall Sewer Works at Crossness have been illuminated. 
In surgery, the magnesium light is now freely used in examinations with the speculum. 
In a recent number of ‘ Galignani ’ we read:— 
“ This powerful light has just received a new application in connection with the laryn¬ 
goscope, a small apparatus consisting of two mirrors by means of which the lower parts 
of the larynx may be conveniently brought to view. M. Maisonneuve, being desirous of 
showing his students the manner of using this apparatus, requested Dr. Fournie, the in¬ 
ventor of the improvement we are about to describe, to attend a late clinical lecture of 
his. Dr. Fournie did so, bringing a patient with him who was suffering from a polypus 
situated deep in the throat. This tumour, of the size of a filbert, not only impeded the 
free articulation of sound, but might in the end, by its growth, have rendered respiration 
impossible, and consequently caused death by suffocation. In order to render this patho¬ 
logical phenomenon visible to the students and physicians who crowded the lecture-room, 
M. Fournie made use of the magnesium light. By means of M. Mathieu-Plessy’s lamp, 
especially constructed for the magnesium light, strong luminous rays were projected on 
the mirror placed at the furthest end of the fauces, and thence reflected into the larynx 
and the trachea. These parts being thus powerfully illuminated, were visibly depicted 
on the mirror; but the image was necessarily small, the mirror not being more than two 
centimetres 'square. But on a bi-convex lens being placed before the patient’s mouth, 
the image became so enlarged, that every one could distinguish it from a distance of a 
few metres. These two applications of important scientific discoveries and contrivances 
combined are highly interesting ; in the first place, by the aid of the magnesium light, 
the exact site of the slightest sore in the upper respiratory organs may be discovered by 
physicians ; and in the second place, the same may be rendered visible to a numerous 
audience.” 
One of the peculiarities of the magnesium light is, that it displays colour as in sun¬ 
shine. This may be tested, and a very interesting effect produced, by burning some 
wire in a garden or conservatory at night. This peculiarity we learn, from the 1 British 
Journal of Photography,’ is being turned to practical account:— 
“ The magnesium lamp promises quickly to become a regular article of furniture in 
every silk-mercer’s show-room. A dyer, of Paris, some months ago, saw the magnesium 
light for the first time, and discovering at once that its rays left colours unaffected, ex¬ 
claimed, ‘ This is just what we have long wanted.’ Even in Paris there are many days 
in winter when those who deal with delicate shades of colour are utterly at a loss to dis¬ 
criminate between tint and tint, but the magnesium light has completely removed the 
difficulty. Now, whether it be foggy or night, any question as to colour is in a moment 
set at rest in the flame of a bit of magnesium wire.” 
The strength of the magnesium light, coupled with its easy production, qualifies it for 
extensive employment in commerce and war. Unlike the electric and oxy-hydrogen 
lights, it involves no cumbrous and troublesome apparatus. With a coil of the wire in 
his waistcoat pocket and a few matches, an Alpine explorer has instant means for making 
his whereabouts known at night. The light has been seen at a distance of twenty-eight 
