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hour to any of his audience, your lecturer’s efforts will 
not have been altogether in vain. But to each such 
happy individual he would express the hope that, as you 
have resembled Mr. Fuller in your experience of life, so 
may you emulate him in your liberality at death. In 
short, I would conclude almost in the words of old Bishop 
Andrews : “ Unum operze mez pretium abs te peto, hoc 
autem vehementer expeto, ut mei pecatoris meorumque in 
precibus interdum memor sis.” Which being interpreted is : 
“ For these my efforts I beg but one thing in return, and 
this I beg most earnestly, viz. that you will now and then 
remember me a sinner against your patience and for- 
bearance in your prayers, and that you will also be mind- 
ful of our professorships in your wills.” 
The following Table of the principal items of original 
work done by our Professors, taken in connection with 
their long series of laboratory notes, forms a monument 
of the intellectual activity, the manual dexterity, and the 
persevering industry, developed in the laboratories of the 
Royal Institution :— 
DAVY 
1806 Chemical Agencies of Electricity, 
1807. Decomposition of Potash. . 
1810 Chlorine. 
1812. Discourse on Radiant or Ethereal Matter, 
1813 Iodine. 
1815-6 Researches on Fire-damp and Flame. 
1817 The Safety Lamp. 
FARADAY 
1820 Alloys of Steel. 
1821 History of Electro-magnetism. 
es Magnetic Rotations. 
1823 Liquefaction of Chlorine and other Gases. 
1825-6 New Compounds of Carbon and Hydrogen, 
1825-9 Manufacture of Optical Glass. 
1831 Vibrating Surfaces. 
* Magneto-Electricity. 
1832. ‘Terrestrial Magneto-Electric Induction 
1833 Identity of Electricities. 
1834 Electro-Chemical Decomposition, 
$ Electricity ofthe Voltaic Pile. 
1835 The Extra Current, 
1837-8 Frictional Electricity. 
~ Specific Inductive Capacity. 
1845-8 Magnetisation of Light. 
Lines of Magnetic Force. 
Tagnetic Condition of all Matter. 
_ magnetism. 
i agne-Crystallic Action, 
1849-50 Magnetism of Flame and Gases. 
Atmospheric Magnetism. 
1856 Relations of Gold and other Metals to Light. 
1860 The Regelation of Ice. 
TYNDALL 
1853 Transmission of Heat through Organic Substances. 
1854 Vibrations due to Contact of Bodies at Different Tem- 
peratures. 
1855 Researches on Diamagnetic Force. 
1856 Slaty Cleavage. 
1857-8 Physical Properties of Ice and Glaciers. 
1859-63 Absorption and Radiation of Heat by Gases. 
1865 Calorescence, EA 
1866-7 Action of Heat of high Refrangibility. 
1868-9 Yormation of Clouds. 
s Colour and Polarisation of the Sky. 
1870 Smoke and Dust Respirator. 
FRANKLAND 
1863-6 Synthesis of Acids of the Lactic Series, 
1863 Mercury-methyl, Mercury-ethyl, and Mercury-amyl. 
1864 Transformation of Organo-Mercury Compounds into 
Organo-Zinc Compounds. 
Combustion of Iron in Compressed Oxygen. 
Synthesis of Acids of the Acrylic Series. 
Synthesis of Fatty Acids. 
NATURE 
265 
1866 New Organic Radical Oxatyl. 
1866 The Source of Muscular Power. Potential Energy in 
various kinds of Food. 
1867 Source of Light in Flame. Effect of Pressure upon 
Luminosity of Flame, 
THE GROWTH AND MIGRATIONS OF 
HELMINTHS 
af migration of helminths is one of the most inte- 
resting discoveries of modern zoology. These wornis, 
generally parasitic, must often, in order to complete their 
growth, pass from one animal into another. This passage 
is of course accomplished by chance, as when one 
animal devours the whole or part of another, in which 
the helminth at a certain stage may be imbedded. 
It is known that sheep attacked by sturdy, have in 
their brain a little worm, the Cenurus. That worm 
when it is eaten by a dog is not digested by him, but 
grows in the intestine under the form of a peculiar tenia. 
It is also known that the tenia, or tape-worm, is gene- 
rated by the growth of the human cysticercus of the pig. 
Very interesting researches have been made by several 
physiologists on that subject. 
M. Villot has filled up many gaps in the history of 
the growth of the gordins. The gordins (Miller) are 
aquatic worms, whose body is very long and slim, the 
extremities being obtuse, 
The form of the embryo is very different from that of 
the full-grown animal. It is a microscopic worm, cylin- 
drical, not more than 0'209 mm, (0'00807 in.) in length, 
by 0'049 mm, (0'00177 in.) in breadth, and on which a 
head and a tail can be easily discerned. The head, as 
big as the body, is quite retractile ; it has a triple crown 
of prickles, and is terminated in front by a kind of trunk 
or sucker, which is kept rigid by three strong needles 
that serve it as support ; the head, in its motion of pro- 
traction and retraction, turns from its extremity to its base 
as a glove, and during that time the points of the prickles 
describe half a circle. When the head is out of the body, 
the point is directed backward; when it is retracted into 
the interior of the body the reverse takes place. 
Numerous transverse folds exist on the body ; they are 
close to one another and regular as real rings. The tail, 
not quite so broad as the body, is separated from it by a 
deep groove. 
The great difference between those embryos that 
are free in the water and the worms which grow out 
of them after many migrations into the interior of several 
animals,. deserves to be noticed. The embryo after 
leaving its egg for the water in which it must live, has 
little means of locomotion. Its tail, cylindrical and 
scarcely moveable, is useless to it for swimming, so that 
it may be driven by any current. It probably sticks to 
pebbles, or tothe roots or stems of aquatic plants, where 
it waits for the larvee, whose parasite it is to become. 
The author has verified these statements by putting 
in the same vessel several embryos with larvee of tipulars 
(Corethra, Fanipus, Chironomus), and has seen the former 
encyst themselves in the insects. The worm penetrates 
with its cephalic prickles into those larve, the teguments 
of which have little power of resistance. It continues 
the operation, piercing through more and more, till the 
membranes get solidified around it and form areal cyst, 
shut up at the posterior post. It continues to penetrate 
the body of the larvee, lengthening its cyst and proceeds. 
Those cysts do not grow normally in the interior of 
insects as has been believed up to this time, but in certain 
fishes, and particularly in the loaches (Coditis darbatula) 
and minnows (Phoxinus lavis). Fishes are generally very 
fond of the larvze of insects, but most especially for the 
larve of Chironomus, It is precisely in those larvae, as 
we have already seen, that the embryos of gordins encyst 
themselves. By swallowing them, the fish swallows at 
