- Email: [email protected]
Writing machine for the blind
Dee., 1877.]
Writing Machine for the Blind.
367
W r i t i n g M a c h i n e for t h e B l i n d . - - M . Reeordon, of Geneva, has invented a machine which enables the blind to write, both in characters which can be read by their blind companions, and in ordinary letters. He proposes to publish a journal for the blind, of which the first number will be issued at Geneva, Jan. 1, 1878.--Lea Mondes. C. Electric Conductivity of Trees,--Th. du Moncel reports a series of careful experiments upon the conductibility of trees. He finds a resistance, when the leaves are the points of contact, equivalent to from 200,000 to 400,000 kilometres of telegraph wire. In moderately large trees, at a height of 7 or 8 metres on the trunk, it is about 3000 kilometres.--Comptes Hendus. C.
Electrical Relations of Capillary Constants,--M. Lippmann reports experiments, conducted in the laboratory of Jamin, which show that for every value of electro-motive force, the capillary constant (or superficial tension) has only one value, whatever may be the chemical composition of the liquid. In other words, if the electro-motive force of two different combinations is the same, the capillary constant is also the same.--Comptes Hendus. C. Vapor Density and Elasticity.--Alexander l~orton publishes some ingenious and interesting experiments on the maximum elasticity and density of vapors. He finds that absolute alcohol and chloroform vapors have equal elasticity at a temperature a little above that of melted lead; that there is a temperature at which steam and bisulphide of carbon have equal elasticities; that cloroform may be vaporized and re-liquefied at a still higher temperature.--Proc. Phil. Soe., Glasgow, v.x. C. Meteoric R u p t u r e . - - S h o w e r s of meteoric stones have been attributed, by Haidinger and others, to the joint attraction of ~eparate bodies, forming a cluster which enters the atmosphere as a single mass. Maskelyne supposed that the detonations in the upper air, were due to the expansion of the outer portions, while the interior retained the extreme cold of the celestial spaces. Benzenberg sought an explanation in electric discharges, produced by violent friction. Daubr6e has experimented with dynamite and steel, to show that " t h e fragmentary form of meteoric irons may be attributed to a rupture under the action of strongly compressed gases."--Gomptes Rendus. C.
Writing Machine for the Blind.
367
W r i t i n g M a c h i n e for t h e B l i n d . - - M . Reeordon, of Geneva, has invented a machine which enables the blind to write, both in characters which can be read by their blind companions, and in ordinary letters. He proposes to publish a journal for the blind, of which the first number will be issued at Geneva, Jan. 1, 1878.--Lea Mondes. C. Electric Conductivity of Trees,--Th. du Moncel reports a series of careful experiments upon the conductibility of trees. He finds a resistance, when the leaves are the points of contact, equivalent to from 200,000 to 400,000 kilometres of telegraph wire. In moderately large trees, at a height of 7 or 8 metres on the trunk, it is about 3000 kilometres.--Comptes Hendus. C.
Electrical Relations of Capillary Constants,--M. Lippmann reports experiments, conducted in the laboratory of Jamin, which show that for every value of electro-motive force, the capillary constant (or superficial tension) has only one value, whatever may be the chemical composition of the liquid. In other words, if the electro-motive force of two different combinations is the same, the capillary constant is also the same.--Comptes Hendus. C. Vapor Density and Elasticity.--Alexander l~orton publishes some ingenious and interesting experiments on the maximum elasticity and density of vapors. He finds that absolute alcohol and chloroform vapors have equal elasticity at a temperature a little above that of melted lead; that there is a temperature at which steam and bisulphide of carbon have equal elasticities; that cloroform may be vaporized and re-liquefied at a still higher temperature.--Proc. Phil. Soe., Glasgow, v.x. C. Meteoric R u p t u r e . - - S h o w e r s of meteoric stones have been attributed, by Haidinger and others, to the joint attraction of ~eparate bodies, forming a cluster which enters the atmosphere as a single mass. Maskelyne supposed that the detonations in the upper air, were due to the expansion of the outer portions, while the interior retained the extreme cold of the celestial spaces. Benzenberg sought an explanation in electric discharges, produced by violent friction. Daubr6e has experimented with dynamite and steel, to show that " t h e fragmentary form of meteoric irons may be attributed to a rupture under the action of strongly compressed gases."--Gomptes Rendus. C.