Manchester, 14 July 1858 

Dear Moor, 

Up here we are now in the middle of the balance-sheet and 
hence I haven’t had the leisure to write to you at greater length. I 
hope that your little Tussy* is better. Gumpert tells me that in the 
English climate whooping-cough is seldom dangerous and, though 
usually chronic, is benign. All the cases they’ve had in the hospital 
so far have ended well. He gave me both the reports (Marei’s) this 
hospital has so far produced. They are highly scientific and I wish 

a See also this volume, p. 322. - > F. Engels, “The Indian Army’. - ¢ A. Humboldt, ‘A 
Private Letter to Mr. Julius Froebel’, New-York Daily Tribune, No. 5335, 27 May 
1858. - 4 J. Frdébel, Aus America. - ¢ Eleanor Marx 

I had had material of this kind when I was writing my book.’ I 
also have copies of it for you which I shall be sending; individual 
bits may come in useful for your chapter on wage labour. No 
doubt you will derive some amusement from Marei’s grandiose 
conception and sanguine expectations. 

Have neither seen nor heard of the statements by Mr Turr, etc. 
The Star is not much read up here. So I'd be glad if you would 
just send The Free Press’ and also, if possible, a copy for Lupus, 
who is still in Buxton, whither he was sent by Borchardt, and 
where, out of boredom, he may well do more walking than is good 
for his leg. 

The two letters from New York which you mention in your last 
were not enclosed.*”! 

Apropos. Kindly let me have Hegel’s Philosophy of Nature° as 
promised. I am presently doing a little physiology which I shall 
combine with comparative anatomy. Here one comes upon highly 
speculative things, all of which, however, have only recently been 
discovered; I am exceedingly curious to see whether the old man 
may not already have had some inkling of them. This much is 
certain: were he today to write a Philosophy of Nature, subjects 
would come flocking in on him from all directions. One has no 
idea, by the way, of the progress made in the natural sciences 
during the past, 30 years. Two things have been crucial where 
physiology is concerned: 1. the tremendous development of 
organic chemistry, 2. the microscope, which has been properly 
used only during the past 20 years. This last has produced even 
more important results than chemistry; what has been chiefly 
responsible for revolutionising the whole of physiology and has 
alone made comparative physiology possible is the discovery of the 
cell—in plants by Schleiden and in animals by Schwann (about 
1836). Everything consists of cells. The cell is Hegelian ‘being in 
itself? and its. development follows the Hegelian process step by 
step right upto the final emergence of the ‘idea’—i.e. each 
completed organism. 

Another result that would have delighted old Hegel is the 
correlation of forces in physics, or the law whereby mechanical 
motion, i.e. mechanical force (e.g. through friction), is, in given 
conditions, converted into heat, heat into light, light into chemical 
affinity, chemical affinity (e.g. in the voltaic pile) into electricity, 
the latter into magnetism. These transitions may also take place 
a The Condition of the Working-Class in England - > 1. Tir, “To the Editor of the Presse 

d’Orient’, The Free Press, No. 18, 30 June 1858. - ¢ G. W. F. Hegel, Vorlesungen über die 
Naturphilosophie... 

differently, backwards or forwards. An Englishman* whose name I 
can’t recall has now shown that these forces pass from one to the 
other in quite specific quantitative proportions so that e.g. a 
certain quantity of one, e.g. electricity, corresponds to a certain 
quantity of each of the others, e.g. magnetism, light, heat, 
chemical affinity (positive or negative—combining or separating) 
and motion. The idiotic theory of latent heat is thus disposed of. 
But isn’t this splendid material proof of how the reflex categories 
dissolve one into the other? 

This much is certain—comparative physiology gives one a 
healthy contempt for man’s idealistic arrogance in regard to other 
animals. At every step it is forcibly brought home to one how 
completely his structure corresponds to that of other mammals; he 
has basic features in common with all vertebrates and even—if less 
distinctly —with insects, crustaceans, tapeworms, etc. Here too 
Hegel’s stuff about the qualitative leap in the quantitative sequence 
fits in very nicely. Finally, with the most primitive infusoria, one 
reaches the original form, the single cell existing independently, 
which again is not perceptibly distinguishable from the lowest 
vegetable life (single-celled fungi such as those causing disease in 
potatoes, the vine, etc., etc.) or, at a higher stage of development, 
from the germ right up to and including the human ovum and 
spermatozoon, and is identical in appearance to the separate cells 
in the living body (blood corpuscles, the cells of the epidermis and 
mucous membrane, secreting cells in the glands, kidneys, etc., 
etc.). 

Some time.you might also let me know what sort of a disease 
dyspepsia crapulosa” is. This isn’t, as it happens, a bad joke but a 
scientifically recognised term. 

If The Times has any particulars about India tomorrow, we shall 
see what can be done for the Tribune, otherwise it will be no go. So 
you'll see from tomorrow’s Times more or less what can be 
expected. 

Warm regards to the Famicy. 
Your 

F. E. 
The acceptance business successfully concluded.