110 Progress in Science. (January, 
effect depends more on the velocity than on the momentum or vis viva of the 
surge. 4th. That it is very rash to generalise from observations on the breaking 
of structures by a blow in one case to others even nearly allied without care- 
fully considering all the details. 
In a paper by Mr. H. Wild on an improved method of filling barometer 
tubes without the necessity of boiling the mercury and without the danger of 
breaking the tube, the author describes a method of purifying mercury from 
zinc and other metals which are not easily removed by distillation. Take 
1ooo grms. of that metal, pour itintoa strong flask capable of holding 2000 grms. 
of water. Take, next, 30 grms. of a solution of chloride of iron (made up of 
I part of the dry salt and 3 parts of water), add this to the mercury, and, after 
having closed the flask with a cork, shake it vigorously until the metal is so 
finely divided that with the naked eye no more globules can be seen. Water 
is next poured into the flask, and the contents, having been well agitated, are 
left for a moment to settle, and the impure solution poured of; this operation 
is repeated twice, after which the greyish mass of very finely divided metal is 
poured into a porcelain basin, which, having been placed on a water-bath, is 
made dry, and next brought to its normal state of aggregation by rubbing in a 
glazed porcelain mortar. The metal is next filtered through good tough 
writing-paper wherein a perforation has been made with a needle. 
Dr. Sézille has described a new process of panification. The wheat is first 
deprived of its outer cover, or husk, by means of properly constructed machinery ; 
the decorticated grain is next several times acted upon by tepid water at about 
80° for the first bath and 40° for the subsequent ones, whereby the gummo- 
resinous cover of the grain is dissolved and removed. This removal is neces- 
sary on account of the fact that this substance becomes very deep brown, 
almost blackish, coloured by fermentation of the dough; the grain at the same 
time absorbs from 65 to 70 per cent of water, and is then reduced to a paste 
by means of machinery very similar to that used in chocolate mills. This 
perfeGly white paste is next leavened, and after fermentation is ready for 
baking. By this process, from the same quantity of grain which by the usual 
process only yields 108 to 110 kilos. of bread, the yield is increased to 145 kilos. 
of very superior quality and far greater nutritive power; moreover, a very con- 
siderable saving of labour and expenses connected therewith is effected by the 
application of this new process, which has beenthoroughly tested by competent 
and independent scientific as well as practical men. 
A method of coating metallic objects with a very durable black-brown varnish 
is given by Dr. C. Puscher. On the bottom of a cylindrical cast-iron vessel, 
x8 inches high, is placed a layer, } inch thick, of coal-dust ; upon this is placed 
an iron grating, and thereon are put the iron, steel, or other metallic objects 
intended to be coated with the varnish. The vessel, having been first closed 
with a well-fitting lid, is next placed on a bright coke fire, and heated for about 
a quarter of an hour just to incipient red heat. The vessel is then removed 
from the fire, and on the lid being removed, after about ten minutes, the 
metallic objects will be found coated very uniformly with a good and durable 
varnish, which resists bending, as well as a high temperature, without cracking 
or coming off. Very small objects, such as hooks-and-eyes, for instance, are 
better placed along with some coal-dust in a coffee-roasting apparatus, and 
this turned, as is usual in the roasting of coffee, until the metallic objects have 
obtained the desired depth of colour and are uniformly coated with the varnish. 
By the use of types made of an elastic material, A. Ae. Wilbaux prints on 
glass by means of fluoride of calcium incorporated in printing ink; the glass 
thus printed on is next treated at a suitable temperature with sulphuric acid, 
and after having been washed with water it contains in an indelible engraving 
the figures of the types. 
An elaborate essay on the pigments and dyes known to and used by the 
ancients has been published by M. E. Rousset. From the contents it appears 
that the author’s primary objeé is to prove that the ancients were not so 
ignorant in industrial matters as is commonly supposed to be the case. 
Among the white pigments they were acquainted with white-lead, which, 
