i would send you more , but i am uneasy about our travelling expenses ; for though pyotr petrovitch has been so kind as to undertake part of the expenses of the journey , that is to say , he has taken upon himself the conveyance of our bags and big trunk ( which will be conveyed through some acquaintances of his ) , we must reckon upon some expense on our arrival in petersburg , where we ca n't be left without a halfpenny , at least for the first few days .