624 PRACTICE OF PHYSIC. 



the faulty state of ossification, seemingly depending upon the 

 deficiency of that matter which should be deposited in the mem- 

 branes which are destined to become bony, and should give 

 them their due firmness, and bony hardness. It appears that 

 this matter is not supplied in due quantity ; but that, in place 

 of it, a matter fitted to increase their bulk, particularly in the 

 epiphyses, is applied too largely. What this deficiency of mat- 

 ter depends upon, is difficult to be ascertained. It may be a 

 fault in the organs of digestion and assimilation, which prevents 

 the fluids in general from being properly prepared ; or it may 

 be a fault in the organs of nutrition, which prevents the secre- 

 tion of a proper matter to be applied. With respect to the lat- 

 ter, in what it may consist, I am entirely ignorant, and cannot 

 even discern that such a condition exists ; but the former cause, 

 both in its nature and existence, is more readily perceived ; and 

 it is probable that it has a considerable influence in the matter, 

 as in rachitic persons, a thinner state of the blood, both during 

 life and after death, so commonly appears. It is this state of 

 the fluids, or a deficiency of bony matter in them, that I con- 

 sider as the proximate cause of the disease ; and which again 

 may in some measure depend upon a general laxity and debility 

 of the moving fibres of the organs that perform the functions of 

 digestion and assimilation. 



MDCCXXVI. There is, however, something still wanting 

 to explain why these circumstances discover themselves at a 

 particular time of life, and hardly ever either before or after a 

 certain period ; and as to this I would offer the following con- 

 jectures. Nature having intended that human life should pro- 

 ceed in a certain manner, and that certain functions should be 

 exercised at a certain period of life only, so it has generally pro- 

 vided, that at that period, and not sooner, the body should be 

 fitted for the exercise of the functions suited to it. To apply 

 this to our present subject, Nature seems to have intended that 

 children should walk at twelve months old ; and accordingly has 

 provided, that against that age, and no sooner, a matter should 

 be prepared fit to give that firmness to the bones which is neces- 

 sary to prevent their bending too easily under the weight of the 

 body. Nature, however, is not always steady and exact in exe- 

 cuting her own purposes; and if, therefore, the preparation of bony 



2 



